<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:19f7398b-a3aa-47f0-bf46-cc3964ae99f2,g:2d88f348-4741-42a6-86ad-074e2960cd10-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://progyny.com/role/ConsolidatedStatementsofChangesinStockholdersEquity" xlink:type="simple" xlink:href="pgny-20250630.xsd#ConsolidatedStatementsofChangesinStockholdersEquity"/>
  <link:definitionLink xlink:role="http://progyny.com/role/ConsolidatedStatementsofChangesinStockholdersEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_c8b073da-3fc8-4dad-87e7-cf0081740336" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_2df4236d-7a41-4df0-8c2d-14daf043063a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_c8b073da-3fc8-4dad-87e7-cf0081740336" xlink:to="loc_us-gaap_StatementTable_2df4236d-7a41-4df0-8c2d-14daf043063a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_8a89d4cf-92f5-456c-b76c-e46d10fd9523" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_2df4236d-7a41-4df0-8c2d-14daf043063a" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_8a89d4cf-92f5-456c-b76c-e46d10fd9523" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_8a89d4cf-92f5-456c-b76c-e46d10fd9523_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_8a89d4cf-92f5-456c-b76c-e46d10fd9523" xlink:to="loc_us-gaap_EquityComponentDomain_8a89d4cf-92f5-456c-b76c-e46d10fd9523_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_567ad00d-6f9c-411e-bcfa-ad973e8ef2ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_8a89d4cf-92f5-456c-b76c-e46d10fd9523" xlink:to="loc_us-gaap_EquityComponentDomain_567ad00d-6f9c-411e-bcfa-ad973e8ef2ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_42ab9b02-1c61-47ac-95d1-2f4f8b4dd8ce" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_567ad00d-6f9c-411e-bcfa-ad973e8ef2ee" xlink:to="loc_us-gaap_CommonStockMember_42ab9b02-1c61-47ac-95d1-2f4f8b4dd8ce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_8deaef75-7572-46c5-bad8-f7a8c468758e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_567ad00d-6f9c-411e-bcfa-ad973e8ef2ee" xlink:to="loc_us-gaap_TreasuryStockCommonMember_8deaef75-7572-46c5-bad8-f7a8c468758e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_06444124-27e0-4c21-b919-6c0d1134ffed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_567ad00d-6f9c-411e-bcfa-ad973e8ef2ee" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_06444124-27e0-4c21-b919-6c0d1134ffed" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_096bc39b-6377-415f-9b1a-b127c7e0f409" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_567ad00d-6f9c-411e-bcfa-ad973e8ef2ee" xlink:to="loc_us-gaap_RetainedEarningsMember_096bc39b-6377-415f-9b1a-b127c7e0f409" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_8a7f055f-e44b-4b6a-b95c-6a9128c67632" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_567ad00d-6f9c-411e-bcfa-ad973e8ef2ee" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_8a7f055f-e44b-4b6a-b95c-6a9128c67632" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_c8b073da-3fc8-4dad-87e7-cf0081740336" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_b7a96e2b-a638-46e4-bbec-3b22ea362e5b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_b7a96e2b-a638-46e4-bbec-3b22ea362e5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_5f945f53-aeee-4440-b92a-64e80b46e0aa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_StockholdersEquity_5f945f53-aeee-4440-b92a-64e80b46e0aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_00bc8960-e720-4ffd-9332-3151c9b2ecbb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_00bc8960-e720-4ffd-9332-3151c9b2ecbb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_89728ed8-76bb-4b96-9e11-0731ac067cbc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_89728ed8-76bb-4b96-9e11-0731ac067cbc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_c7c303f2-c382-4665-965c-55d4339a4f26" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_c7c303f2-c382-4665-965c-55d4339a4f26" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_d7087a05-5d2e-49f3-bf64-52bf376c9e94" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_d7087a05-5d2e-49f3-bf64-52bf376c9e94" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_0a64c4f0-053d-4d15-a6cd-b13af88503a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_0a64c4f0-053d-4d15-a6cd-b13af88503a0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_f4d05e58-601f-439f-848a-400fc0fc7ac7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_f4d05e58-601f-439f-848a-400fc0fc7ac7" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_5d357c2a-1590-4cf1-97de-41364f74c639" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_230bba9d-9b29-436a-a21e-12f10c49ca5a" xlink:to="loc_us-gaap_NetIncomeLoss_5d357c2a-1590-4cf1-97de-41364f74c639" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_51e8a8a1-9525-46b3-a5ab-3fa583df522e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_cb415446-b38a-4e5e-9b92-3e68504cb291" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/SignificantAccountingPoliciesRevenueRecognitionDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#SignificantAccountingPoliciesRevenueRecognitionDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/SignificantAccountingPoliciesRevenueRecognitionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_99209692-8dec-44e9-a553-2938298e1840" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_729e3417-34ea-4829-bc08-6b8023ab1c17" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_99209692-8dec-44e9-a553-2938298e1840" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_729e3417-34ea-4829-bc08-6b8023ab1c17" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_3b16dac0-6db0-4d3d-bb50-9673069cb9d2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_729e3417-34ea-4829-bc08-6b8023ab1c17" xlink:to="loc_srt_RangeAxis_3b16dac0-6db0-4d3d-bb50-9673069cb9d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_3b16dac0-6db0-4d3d-bb50-9673069cb9d2_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_3b16dac0-6db0-4d3d-bb50-9673069cb9d2" xlink:to="loc_srt_RangeMember_3b16dac0-6db0-4d3d-bb50-9673069cb9d2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_d72b2ff1-da2c-442f-a7ff-0a898b6f2e86" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_3b16dac0-6db0-4d3d-bb50-9673069cb9d2" xlink:to="loc_srt_RangeMember_d72b2ff1-da2c-442f-a7ff-0a898b6f2e86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_7811deca-1d34-42b2-a06b-91eb6d3a3452" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d72b2ff1-da2c-442f-a7ff-0a898b6f2e86" xlink:to="loc_srt_MinimumMember_7811deca-1d34-42b2-a06b-91eb6d3a3452" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_7c2fead2-3a4c-483e-af60-be7781f18b42" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d72b2ff1-da2c-442f-a7ff-0a898b6f2e86" xlink:to="loc_srt_MaximumMember_7c2fead2-3a4c-483e-af60-be7781f18b42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_RevenueFromContractWithCustomerTerm_61023eaa-138a-4975-9502-a7ddcdcecb79" xlink:href="pgny-20250630.xsd#pgny_RevenueFromContractWithCustomerTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_99209692-8dec-44e9-a553-2938298e1840" xlink:to="loc_pgny_RevenueFromContractWithCustomerTerm_61023eaa-138a-4975-9502-a7ddcdcecb79" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_ContractTerminationNoticePeriod_4f4703f9-ccb6-445c-927e-9566862b98e5" xlink:href="pgny-20250630.xsd#pgny_ContractTerminationNoticePeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_99209692-8dec-44e9-a553-2938298e1840" xlink:to="loc_pgny_ContractTerminationNoticePeriod_4f4703f9-ccb6-445c-927e-9566862b98e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_CustomerPaymentTerms_36271e0e-dc84-4650-89fe-616d4b7cbfbd" xlink:href="pgny-20250630.xsd#pgny_CustomerPaymentTerms"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_99209692-8dec-44e9-a553-2938298e1840" xlink:to="loc_pgny_CustomerPaymentTerms_36271e0e-dc84-4650-89fe-616d4b7cbfbd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_RevenueRemainingPerformanceObligationRemainingContractTerm_3f938e80-5960-4486-847e-443339db30c9" xlink:href="pgny-20250630.xsd#pgny_RevenueRemainingPerformanceObligationRemainingContractTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_99209692-8dec-44e9-a553-2938298e1840" xlink:to="loc_pgny_RevenueRemainingPerformanceObligationRemainingContractTerm_3f938e80-5960-4486-847e-443339db30c9" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/SignificantAccountingPoliciesCostofServicesDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#SignificantAccountingPoliciesCostofServicesDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/SignificantAccountingPoliciesCostofServicesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_b950944f-74bf-421d-a918-d14fa92b4465" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_02f18cd8-cc79-4910-b1cf-6662aa868934" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_b950944f-74bf-421d-a918-d14fa92b4465" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_02f18cd8-cc79-4910-b1cf-6662aa868934" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_9c3ab4da-cd62-48c1-a265-4e70bfdb43e5" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_02f18cd8-cc79-4910-b1cf-6662aa868934" xlink:to="loc_srt_RangeAxis_9c3ab4da-cd62-48c1-a265-4e70bfdb43e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_9c3ab4da-cd62-48c1-a265-4e70bfdb43e5_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_9c3ab4da-cd62-48c1-a265-4e70bfdb43e5" xlink:to="loc_srt_RangeMember_9c3ab4da-cd62-48c1-a265-4e70bfdb43e5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_d52ce7b8-0bb4-432f-b2f2-cf4d8fbf02fb" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_9c3ab4da-cd62-48c1-a265-4e70bfdb43e5" xlink:to="loc_srt_RangeMember_d52ce7b8-0bb4-432f-b2f2-cf4d8fbf02fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_f51594b2-fcc9-423f-a00b-7e237e2c2b7c" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d52ce7b8-0bb4-432f-b2f2-cf4d8fbf02fb" xlink:to="loc_srt_MinimumMember_f51594b2-fcc9-423f-a00b-7e237e2c2b7c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_af68795e-7cd1-437d-bb09-298dea1855d6" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d52ce7b8-0bb4-432f-b2f2-cf4d8fbf02fb" xlink:to="loc_srt_MaximumMember_af68795e-7cd1-437d-bb09-298dea1855d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_ContractTermClinics_194cfb0c-2e0c-4275-aec2-879d18d41ed9" xlink:href="pgny-20250630.xsd#pgny_ContractTermClinics"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_b950944f-74bf-421d-a918-d14fa92b4465" xlink:to="loc_pgny_ContractTermClinics_194cfb0c-2e0c-4275-aec2-879d18d41ed9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_CostOfGoodsAndServiceSoldSpecialtyPharmaciesContractTerm_5c38a7d4-0bb1-4564-b26f-325084f2417a" xlink:href="pgny-20250630.xsd#pgny_CostOfGoodsAndServiceSoldSpecialtyPharmaciesContractTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_b950944f-74bf-421d-a918-d14fa92b4465" xlink:to="loc_pgny_CostOfGoodsAndServiceSoldSpecialtyPharmaciesContractTerm_5c38a7d4-0bb1-4564-b26f-325084f2417a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_BillingTerms_b33cb9b2-0621-4f79-92dc-06705b5995b2" xlink:href="pgny-20250630.xsd#pgny_BillingTerms"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_b950944f-74bf-421d-a918-d14fa92b4465" xlink:to="loc_pgny_BillingTerms_b33cb9b2-0621-4f79-92dc-06705b5995b2" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/RevenueDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#RevenueDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/RevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_18f7d637-506c-4613-b76b-e14d1b63c16a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_89cd9751-9bff-4ce3-9cf9-152a5ac58984" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_18f7d637-506c-4613-b76b-e14d1b63c16a" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_89cd9751-9bff-4ce3-9cf9-152a5ac58984" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_02510671-ea0a-42be-b868-5f811226db6b" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_89cd9751-9bff-4ce3-9cf9-152a5ac58984" xlink:to="loc_srt_ProductOrServiceAxis_02510671-ea0a-42be-b868-5f811226db6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_02510671-ea0a-42be-b868-5f811226db6b_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_02510671-ea0a-42be-b868-5f811226db6b" xlink:to="loc_srt_ProductsAndServicesDomain_02510671-ea0a-42be-b868-5f811226db6b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_8b547b23-35a2-4f46-8947-79cfafd90c23" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_02510671-ea0a-42be-b868-5f811226db6b" xlink:to="loc_srt_ProductsAndServicesDomain_8b547b23-35a2-4f46-8947-79cfafd90c23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_FertilityBenefitServicesMember_4cdd3918-1c3a-4e6b-9b6d-afcd9beabb93" xlink:href="pgny-20250630.xsd#pgny_FertilityBenefitServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_8b547b23-35a2-4f46-8947-79cfafd90c23" xlink:to="loc_pgny_FertilityBenefitServicesMember_4cdd3918-1c3a-4e6b-9b6d-afcd9beabb93" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_PharmacyBenefitServicesMember_004f8ec1-bc5a-4d9b-861a-355e07529f36" xlink:href="pgny-20250630.xsd#pgny_PharmacyBenefitServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_8b547b23-35a2-4f46-8947-79cfafd90c23" xlink:to="loc_pgny_PharmacyBenefitServicesMember_004f8ec1-bc5a-4d9b-861a-355e07529f36" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_aeebdea6-5889-4e6e-bd89-ec9fb4ec3fc0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_18f7d637-506c-4613-b76b-e14d1b63c16a" xlink:to="loc_us-gaap_RevenuesAbstract_aeebdea6-5889-4e6e-bd89-ec9fb4ec3fc0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_7d904d44-dcca-4bb5-ab98-3732242716e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_aeebdea6-5889-4e6e-bd89-ec9fb4ec3fc0" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_7d904d44-dcca-4bb5-ab98-3732242716e7" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/FairValueofFinancialInstrumentsDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#FairValueofFinancialInstrumentsDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/FairValueofFinancialInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_193b9974-046a-42ea-bd23-04879c8c116e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_749a12c4-5d3d-41eb-b98f-295c9074783c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_193b9974-046a-42ea-bd23-04879c8c116e" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_749a12c4-5d3d-41eb-b98f-295c9074783c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAxis_e28922dd-76b1-4ccc-92dd-b5efe452cd9e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_749a12c4-5d3d-41eb-b98f-295c9074783c" xlink:to="loc_us-gaap_CashAndCashEquivalentsAxis_e28922dd-76b1-4ccc-92dd-b5efe452cd9e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_e28922dd-76b1-4ccc-92dd-b5efe452cd9e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_e28922dd-76b1-4ccc-92dd-b5efe452cd9e" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_e28922dd-76b1-4ccc-92dd-b5efe452cd9e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_bff27122-60ad-4ffd-862e-b3ffc6999675" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_e28922dd-76b1-4ccc-92dd-b5efe452cd9e" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_bff27122-60ad-4ffd-862e-b3ffc6999675" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MoneyMarketFundsMember_219a338b-5f17-4fab-bd47-08cb98a5c7c5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MoneyMarketFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_bff27122-60ad-4ffd-862e-b3ffc6999675" xlink:to="loc_us-gaap_MoneyMarketFundsMember_219a338b-5f17-4fab-bd47-08cb98a5c7c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_3de6b48a-b839-458f-9e4e-8a9c6bab493d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_749a12c4-5d3d-41eb-b98f-295c9074783c" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_3de6b48a-b839-458f-9e4e-8a9c6bab493d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_3de6b48a-b839-458f-9e4e-8a9c6bab493d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_3de6b48a-b839-458f-9e4e-8a9c6bab493d" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_3de6b48a-b839-458f-9e4e-8a9c6bab493d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_82860b7d-0420-4f13-905d-651154406237" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_3de6b48a-b839-458f-9e4e-8a9c6bab493d" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_82860b7d-0420-4f13-905d-651154406237" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_aee12ec9-e0ac-489d-a540-82c6101d748e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_82860b7d-0420-4f13-905d-651154406237" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_aee12ec9-e0ac-489d-a540-82c6101d748e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_4346384e-02e2-4f99-b4a2-0df738bbc46b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_82860b7d-0420-4f13-905d-651154406237" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_4346384e-02e2-4f99-b4a2-0df738bbc46b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_118feb9a-cdd9-42e2-bd50-33abb04da682" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_82860b7d-0420-4f13-905d-651154406237" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_118feb9a-cdd9-42e2-bd50-33abb04da682" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_a997cbe9-c24b-4bb0-939f-d292249df00a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_749a12c4-5d3d-41eb-b98f-295c9074783c" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_a997cbe9-c24b-4bb0-939f-d292249df00a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_a997cbe9-c24b-4bb0-939f-d292249df00a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_a997cbe9-c24b-4bb0-939f-d292249df00a" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_a997cbe9-c24b-4bb0-939f-d292249df00a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_b15f799b-5566-4966-8ab9-ed738739179b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_a997cbe9-c24b-4bb0-939f-d292249df00a" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_b15f799b-5566-4966-8ab9-ed738739179b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_0b5e2ae2-1a81-4ea1-8f99-2553588a142d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_b15f799b-5566-4966-8ab9-ed738739179b" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_0b5e2ae2-1a81-4ea1-8f99-2553588a142d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_44f10552-c934-4788-b251-2411cb6e4aa2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_193b9974-046a-42ea-bd23-04879c8c116e" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_44f10552-c934-4788-b251-2411cb6e4aa2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_5e677277-347d-4613-935a-39ddbb62e0cc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_44f10552-c934-4788-b251-2411cb6e4aa2" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_5e677277-347d-4613-935a-39ddbb62e0cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_20382c87-1bcb-4552-94da-a55b6b48ac36" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_44f10552-c934-4788-b251-2411cb6e4aa2" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_20382c87-1bcb-4552-94da-a55b6b48ac36" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeDebtSecuritiesAvailableForSaleOperating_41374e11-2efe-4845-ab99-203c6a8f32b6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeDebtSecuritiesAvailableForSaleOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_44f10552-c934-4788-b251-2411cb6e4aa2" xlink:to="loc_us-gaap_InterestIncomeDebtSecuritiesAvailableForSaleOperating_41374e11-2efe-4845-ab99-203c6a8f32b6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_0a1e3691-c20f-4ddc-856a-1f7afc639c29" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_44f10552-c934-4788-b251-2411cb6e4aa2" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_0a1e3691-c20f-4ddc-856a-1f7afc639c29" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_37967542-8345-4ff4-a619-f406f3aa1ba3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_44f10552-c934-4788-b251-2411cb6e4aa2" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_37967542-8345-4ff4-a619-f406f3aa1ba3" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/LeasesNarrativeDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#LeasesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/LeasesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeLeaseDescriptionLineItems_63a052be-6091-48a6-9457-b738bafd8bb8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeLeaseDescriptionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeLeaseDescriptionTable_a5270168-3fbf-4a46-ab36-30d59581a7ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeLeaseDescriptionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_63a052be-6091-48a6-9457-b738bafd8bb8" xlink:to="loc_us-gaap_LesseeLeaseDescriptionTable_a5270168-3fbf-4a46-ab36-30d59581a7ec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseContractualTermAxis_bcf535e2-54c1-445a-9253-8941e7fa1148" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_a5270168-3fbf-4a46-ab36-30d59581a7ec" xlink:to="loc_us-gaap_LeaseContractualTermAxis_bcf535e2-54c1-445a-9253-8941e7fa1148" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseContractualTermDomain_bcf535e2-54c1-445a-9253-8941e7fa1148_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LeaseContractualTermAxis_bcf535e2-54c1-445a-9253-8941e7fa1148" xlink:to="loc_us-gaap_LeaseContractualTermDomain_bcf535e2-54c1-445a-9253-8941e7fa1148_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseContractualTermDomain_5f19616f-3bd3-4ba0-aef5-8fcc4102e970" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LeaseContractualTermAxis_bcf535e2-54c1-445a-9253-8941e7fa1148" xlink:to="loc_us-gaap_LeaseContractualTermDomain_5f19616f-3bd3-4ba0-aef5-8fcc4102e970" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_ThroughFifthLeaseYearMember_c0549312-73b1-4535-b911-415c91bcf85e" xlink:href="pgny-20250630.xsd#pgny_ThroughFifthLeaseYearMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LeaseContractualTermDomain_5f19616f-3bd3-4ba0-aef5-8fcc4102e970" xlink:to="loc_pgny_ThroughFifthLeaseYearMember_c0549312-73b1-4535-b911-415c91bcf85e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_AfterFifthLeaseYearMember_9c8ec565-43e8-4e67-8664-7ba3858ce71e" xlink:href="pgny-20250630.xsd#pgny_AfterFifthLeaseYearMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LeaseContractualTermDomain_5f19616f-3bd3-4ba0-aef5-8fcc4102e970" xlink:to="loc_pgny_AfterFifthLeaseYearMember_9c8ec565-43e8-4e67-8664-7ba3858ce71e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_77508061-0026-4496-9514-f93881e85ab8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_a5270168-3fbf-4a46-ab36-30d59581a7ec" xlink:to="loc_srt_StatementScenarioAxis_77508061-0026-4496-9514-f93881e85ab8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_77508061-0026-4496-9514-f93881e85ab8_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_77508061-0026-4496-9514-f93881e85ab8" xlink:to="loc_srt_ScenarioUnspecifiedDomain_77508061-0026-4496-9514-f93881e85ab8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_e77d64be-9324-4186-b179-239091d36417" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_77508061-0026-4496-9514-f93881e85ab8" xlink:to="loc_srt_ScenarioUnspecifiedDomain_e77d64be-9324-4186-b179-239091d36417" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_a4f36418-4fd6-4f3e-9340-c5ccfeecf8a0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_e77d64be-9324-4186-b179-239091d36417" xlink:to="loc_srt_ScenarioForecastMember_a4f36418-4fd6-4f3e-9340-c5ccfeecf8a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_LeaseDescriptionAxis_c6b75041-7723-4532-8875-fc9e01ba04c3" xlink:href="pgny-20250630.xsd#pgny_LeaseDescriptionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_a5270168-3fbf-4a46-ab36-30d59581a7ec" xlink:to="loc_pgny_LeaseDescriptionAxis_c6b75041-7723-4532-8875-fc9e01ba04c3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_LeaseDescriptionDomain_c6b75041-7723-4532-8875-fc9e01ba04c3_default" xlink:href="pgny-20250630.xsd#pgny_LeaseDescriptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_pgny_LeaseDescriptionAxis_c6b75041-7723-4532-8875-fc9e01ba04c3" xlink:to="loc_pgny_LeaseDescriptionDomain_c6b75041-7723-4532-8875-fc9e01ba04c3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_LeaseDescriptionDomain_3e6d61bc-23f7-47b6-ba3d-7bc97af2802b" xlink:href="pgny-20250630.xsd#pgny_LeaseDescriptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_pgny_LeaseDescriptionAxis_c6b75041-7723-4532-8875-fc9e01ba04c3" xlink:to="loc_pgny_LeaseDescriptionDomain_3e6d61bc-23f7-47b6-ba3d-7bc97af2802b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_September2019SubleaseAgreementMember_6b671e24-7d4b-466f-ad45-0a66266ef7bc" xlink:href="pgny-20250630.xsd#pgny_September2019SubleaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_pgny_LeaseDescriptionDomain_3e6d61bc-23f7-47b6-ba3d-7bc97af2802b" xlink:to="loc_pgny_September2019SubleaseAgreementMember_6b671e24-7d4b-466f-ad45-0a66266ef7bc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_Februray2023LeaseAgreementMember_1fda87c9-424f-4bdf-8f2e-f49c51fc9928" xlink:href="pgny-20250630.xsd#pgny_Februray2023LeaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_pgny_LeaseDescriptionDomain_3e6d61bc-23f7-47b6-ba3d-7bc97af2802b" xlink:to="loc_pgny_Februray2023LeaseAgreementMember_1fda87c9-424f-4bdf-8f2e-f49c51fc9928" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_March2025LeaseAgreementMember_c97d6f3e-6be1-41c0-bda3-7cc5f2f56cd1" xlink:href="pgny-20250630.xsd#pgny_March2025LeaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_pgny_LeaseDescriptionDomain_3e6d61bc-23f7-47b6-ba3d-7bc97af2802b" xlink:to="loc_pgny_March2025LeaseAgreementMember_c97d6f3e-6be1-41c0-bda3-7cc5f2f56cd1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseDescriptionAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_63a052be-6091-48a6-9457-b738bafd8bb8" xlink:to="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AreaOfRealEstateProperty_9a8aef1d-4012-4bb9-9c74-5931bd1d2ffb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AreaOfRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:to="loc_us-gaap_AreaOfRealEstateProperty_9a8aef1d-4012-4bb9-9c74-5931bd1d2ffb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_OperatingLeaseBaseRentPerAnnum_e37b037e-224c-4b33-b47b-eda7f93e4147" xlink:href="pgny-20250630.xsd#pgny_OperatingLeaseBaseRentPerAnnum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:to="loc_pgny_OperatingLeaseBaseRentPerAnnum_e37b037e-224c-4b33-b47b-eda7f93e4147" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_33c1c0e5-c62c-4464-92cd-432d23779c7f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_33c1c0e5-c62c-4464-92cd-432d23779c7f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_b7303dcc-6ebc-48f3-aa75-ed12fe0ef64d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:to="loc_us-gaap_OperatingLeaseLiability_b7303dcc-6ebc-48f3-aa75-ed12fe0ef64d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseExpense_6bfbc777-bb52-4c03-ae70-a3658a6bc4a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:to="loc_us-gaap_OperatingLeaseExpense_6bfbc777-bb52-4c03-ae70-a3658a6bc4a0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeasePayments_930f5f1c-1834-4a71-989c-ba07b2f6439a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeasePayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeOperatingLeaseDescriptionAbstract_d052bf55-84f5-408c-8e82-249c0315f9c4" xlink:to="loc_us-gaap_OperatingLeasePayments_930f5f1c-1834-4a71-989c-ba07b2f6439a" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/StockholdersEquityNarrativeDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#StockholdersEquityNarrativeDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/StockholdersEquityNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_6c186089-854c-47cb-a937-d5c682506573" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_6c186089-854c-47cb-a937-d5c682506573" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_1a0ccc99-1fb5-426e-96d5-f1e14cfa5938" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_6c186089-854c-47cb-a937-d5c682506573" xlink:to="loc_srt_ShareRepurchaseProgramAxis_1a0ccc99-1fb5-426e-96d5-f1e14cfa5938" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_1a0ccc99-1fb5-426e-96d5-f1e14cfa5938_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_1a0ccc99-1fb5-426e-96d5-f1e14cfa5938" xlink:to="loc_srt_ShareRepurchaseProgramDomain_1a0ccc99-1fb5-426e-96d5-f1e14cfa5938_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_203fd352-92ab-4e9d-bea5-a9f420be9896" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_1a0ccc99-1fb5-426e-96d5-f1e14cfa5938" xlink:to="loc_srt_ShareRepurchaseProgramDomain_203fd352-92ab-4e9d-bea5-a9f420be9896" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_February2024ShareRepurchaseProgramMember_c949e494-5d02-4342-9564-9392f7934757" xlink:href="pgny-20250630.xsd#pgny_February2024ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_203fd352-92ab-4e9d-bea5-a9f420be9896" xlink:to="loc_pgny_February2024ShareRepurchaseProgramMember_c949e494-5d02-4342-9564-9392f7934757" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_May2024ShareRepurchaseProgramMember_8cdc1cbb-6d59-42b6-a35f-9774f2d7b44a" xlink:href="pgny-20250630.xsd#pgny_May2024ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_203fd352-92ab-4e9d-bea5-a9f420be9896" xlink:to="loc_pgny_May2024ShareRepurchaseProgramMember_8cdc1cbb-6d59-42b6-a35f-9774f2d7b44a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_dddc8339-496a-4a79-b4d5-edc1b14d6c55" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_6c186089-854c-47cb-a937-d5c682506573" xlink:to="loc_us-gaap_StatementClassOfStockAxis_dddc8339-496a-4a79-b4d5-edc1b14d6c55" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_dddc8339-496a-4a79-b4d5-edc1b14d6c55_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_dddc8339-496a-4a79-b4d5-edc1b14d6c55" xlink:to="loc_us-gaap_ClassOfStockDomain_dddc8339-496a-4a79-b4d5-edc1b14d6c55_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_a9d15a4d-2d63-4160-8d8a-106d1651a815" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_dddc8339-496a-4a79-b4d5-edc1b14d6c55" xlink:to="loc_us-gaap_ClassOfStockDomain_a9d15a4d-2d63-4160-8d8a-106d1651a815" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_405cae39-a6f0-45a0-a169-2ca479a337dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_a9d15a4d-2d63-4160-8d8a-106d1651a815" xlink:to="loc_us-gaap_CommonStockMember_405cae39-a6f0-45a0-a169-2ca479a337dc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_16bb198a-706d-41bf-9fb3-4b6964486168" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_16bb198a-706d-41bf-9fb3-4b6964486168" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_155dcee2-989f-414a-910f-225f33e1f433" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:to="loc_us-gaap_TreasuryStockCommonShares_155dcee2-989f-414a-910f-225f33e1f433" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonValue_981223ac-3dd7-443f-b85e-87d81045888c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:to="loc_us-gaap_TreasuryStockCommonValue_981223ac-3dd7-443f-b85e-87d81045888c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_df6da736-cd43-4e28-9d9a-1acc9bb063fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_df6da736-cd43-4e28-9d9a-1acc9bb063fa" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_8e984631-54f0-4c55-ba0a-a2924c5e7bd2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_8e984631-54f0-4c55-ba0a-a2924c5e7bd2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_a327cc6d-f206-40e5-bf00-0d1923fb27cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_6d599edf-dadd-4177-b23d-ff30de14325e" xlink:to="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_a327cc6d-f206-40e5-bf00-0d1923fb27cb" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/StockholdersEquityScheduleofStockBasedCompensationExpenseDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#StockholdersEquityScheduleofStockBasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/StockholdersEquityScheduleofStockBasedCompensationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_06d8c1b8-46de-4ff8-ab4f-a4e9d3765fe6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_dc9356dc-44ef-4306-93b6-3dbe93ced858" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_06d8c1b8-46de-4ff8-ab4f-a4e9d3765fe6" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_dc9356dc-44ef-4306-93b6-3dbe93ced858" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_4b8fb191-e633-4fb5-9bb6-acf58960d7a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_dc9356dc-44ef-4306-93b6-3dbe93ced858" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_4b8fb191-e633-4fb5-9bb6-acf58960d7a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_4b8fb191-e633-4fb5-9bb6-acf58960d7a5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_4b8fb191-e633-4fb5-9bb6-acf58960d7a5" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_4b8fb191-e633-4fb5-9bb6-acf58960d7a5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_126b9806-e524-4fef-89b6-77964611e54a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_4b8fb191-e633-4fb5-9bb6-acf58960d7a5" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_126b9806-e524-4fef-89b6-77964611e54a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfSalesMember_21b4c879-9902-42c9-975c-f03bfbc15cc5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_126b9806-e524-4fef-89b6-77964611e54a" xlink:to="loc_us-gaap_CostOfSalesMember_21b4c879-9902-42c9-975c-f03bfbc15cc5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_497efe0b-50f9-45dd-ac7d-79e5bce2e7e3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_126b9806-e524-4fef-89b6-77964611e54a" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_497efe0b-50f9-45dd-ac7d-79e5bce2e7e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_078802f3-5dae-47bf-a38f-11b878010445" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_126b9806-e524-4fef-89b6-77964611e54a" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_078802f3-5dae-47bf-a38f-11b878010445" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAggregateDisclosuresAbstract_f10306e8-0344-4636-a472-a143da84c590" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAggregateDisclosuresAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_06d8c1b8-46de-4ff8-ab4f-a4e9d3765fe6" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationAggregateDisclosuresAbstract_f10306e8-0344-4636-a472-a143da84c590" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_200fa08e-d463-4d15-8b0e-ee72bf90f7f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAggregateDisclosuresAbstract_f10306e8-0344-4636-a472-a143da84c590" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_200fa08e-d463-4d15-8b0e-ee72bf90f7f8" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/StockholdersEquityScheduleofAccumulatedOtherComprehensiveIncomeDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#StockholdersEquityScheduleofAccumulatedOtherComprehensiveIncomeDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/StockholdersEquityScheduleofAccumulatedOtherComprehensiveIncomeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_7826adc7-137a-416c-bf65-0d291466e4fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_7826adc7-137a-416c-bf65-0d291466e4fa" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_b112d600-808f-4555-abb8-489576162dfc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_7826adc7-137a-416c-bf65-0d291466e4fa" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_b112d600-808f-4555-abb8-489576162dfc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_b112d600-808f-4555-abb8-489576162dfc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_b112d600-808f-4555-abb8-489576162dfc" xlink:to="loc_us-gaap_EquityComponentDomain_b112d600-808f-4555-abb8-489576162dfc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_4487a312-2772-4cf5-99a9-b76945965845" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_b112d600-808f-4555-abb8-489576162dfc" xlink:to="loc_us-gaap_EquityComponentDomain_4487a312-2772-4cf5-99a9-b76945965845" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_c43461ed-6602-4b1c-8de2-e292d254e98b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_4487a312-2772-4cf5-99a9-b76945965845" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_c43461ed-6602-4b1c-8de2-e292d254e98b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_7c7fdccb-56c0-45f1-88e6-216d85b6bcc9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_4487a312-2772-4cf5-99a9-b76945965845" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_7c7fdccb-56c0-45f1-88e6-216d85b6bcc9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_cb80d1d4-57f7-4f40-8aad-3a021136d7f7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_4487a312-2772-4cf5-99a9-b76945965845" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_cb80d1d4-57f7-4f40-8aad-3a021136d7f7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_abd9f09d-b20f-4d5e-b14c-41ca157efafa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_7826adc7-137a-416c-bf65-0d291466e4fa" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_abd9f09d-b20f-4d5e-b14c-41ca157efafa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_abd9f09d-b20f-4d5e-b14c-41ca157efafa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_abd9f09d-b20f-4d5e-b14c-41ca157efafa" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_abd9f09d-b20f-4d5e-b14c-41ca157efafa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_afcef340-070b-4a7c-9cb1-dccd0c9b2050" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_abd9f09d-b20f-4d5e-b14c-41ca157efafa" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_afcef340-070b-4a7c-9cb1-dccd0c9b2050" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_e14e113a-854b-4525-a8af-6e8f21526078" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_afcef340-070b-4a7c-9cb1-dccd0c9b2050" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_e14e113a-854b-4525-a8af-6e8f21526078" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_fff9eca0-cce3-4777-b864-6dd4f2db9d3e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_fff9eca0-cce3-4777-b864-6dd4f2db9d3e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_e45b65bf-a412-497f-9edb-8bf3382fef2b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_fff9eca0-cce3-4777-b864-6dd4f2db9d3e" xlink:to="loc_us-gaap_StockholdersEquity_e45b65bf-a412-497f-9edb-8bf3382fef2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciBeforeReclassificationsNetOfTaxAttributableToParent_1a3e3986-4887-4b55-a63e-59cf37699abc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OciBeforeReclassificationsNetOfTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_fff9eca0-cce3-4777-b864-6dd4f2db9d3e" xlink:to="loc_us-gaap_OciBeforeReclassificationsNetOfTaxAttributableToParent_1a3e3986-4887-4b55-a63e-59cf37699abc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_e57c43fb-6486-4d6a-b89e-f2f8c5eec9f6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_fff9eca0-cce3-4777-b864-6dd4f2db9d3e" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_e57c43fb-6486-4d6a-b89e-f2f8c5eec9f6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_e43f77e1-0fc1-432b-be07-ab6728b547eb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_fff9eca0-cce3-4777-b864-6dd4f2db9d3e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_e43f77e1-0fc1-432b-be07-ab6728b547eb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_1587f1db-8894-4988-95b0-c925b136eee3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax_6c4669d7-e6ba-486c-9630-cc045d334eca" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax_6c4669d7-e6ba-486c-9630-cc045d334eca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax_8884aaaf-0306-4c5d-9b45-3005c1c3a98d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax_8884aaaf-0306-4c5d-9b45-3005c1c3a98d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_13e55290-cc10-4b29-9695-0894e72d103c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_13e55290-cc10-4b29-9695-0894e72d103c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_479c2869-6dc0-493f-9f5f-c726a9047fca" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_479c2869-6dc0-493f-9f5f-c726a9047fca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_d565de76-b940-46b6-841d-2939f6d1c25a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_d565de76-b940-46b6-841d-2939f6d1c25a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_6c48a344-26c4-489c-bef6-6ee3cd8ae5a2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_f72aa797-6d2b-4132-835c-475fb4fa133b" xlink:to="loc_us-gaap_NetIncomeLoss_6c48a344-26c4-489c-bef6-6ee3cd8ae5a2" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/AcquisitionsDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#AcquisitionsDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/AcquisitionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionContingentConsiderationLineItems_35433baf-ee7d-4a74-92a3-752c7f30fa1c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionContingentConsiderationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionContingentConsiderationTable_0bf3e2f0-eac1-4625-beb1-da40e132a65d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionContingentConsiderationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionContingentConsiderationLineItems_35433baf-ee7d-4a74-92a3-752c7f30fa1c" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionContingentConsiderationTable_0bf3e2f0-eac1-4625-beb1-da40e132a65d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_75e33b94-9382-48b1-9211-59a671d58223" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionContingentConsiderationTable_0bf3e2f0-eac1-4625-beb1-da40e132a65d" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_75e33b94-9382-48b1-9211-59a671d58223" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_75e33b94-9382-48b1-9211-59a671d58223_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_75e33b94-9382-48b1-9211-59a671d58223" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_75e33b94-9382-48b1-9211-59a671d58223_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_a66c5910-c9e4-4f47-869e-235a34783dbc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_75e33b94-9382-48b1-9211-59a671d58223" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_a66c5910-c9e4-4f47-869e-235a34783dbc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_BenefitBumpLLCMember_343faaa3-9cb0-4ff8-980a-cff0992d9663" xlink:href="pgny-20250630.xsd#pgny_BenefitBumpLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_a66c5910-c9e4-4f47-869e-235a34783dbc" xlink:to="loc_pgny_BenefitBumpLLCMember_343faaa3-9cb0-4ff8-980a-cff0992d9663" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_AprylGmbHMember_8c547e90-04e3-4f37-b2e8-da8b305ec697" xlink:href="pgny-20250630.xsd#pgny_AprylGmbHMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_a66c5910-c9e4-4f47-869e-235a34783dbc" xlink:to="loc_pgny_AprylGmbHMember_8c547e90-04e3-4f37-b2e8-da8b305ec697" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_b3d006c4-f8df-461f-9773-a7f9577059c1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionContingentConsiderationLineItems_35433baf-ee7d-4a74-92a3-752c7f30fa1c" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_b3d006c4-f8df-461f-9773-a7f9577059c1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EscrowDepositDisbursementsRelatedToPropertyAcquisition1_648be4df-ebe0-4a9b-94dd-a9ea9ddc4794" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EscrowDepositDisbursementsRelatedToPropertyAcquisition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionContingentConsiderationLineItems_35433baf-ee7d-4a74-92a3-752c7f30fa1c" xlink:to="loc_us-gaap_EscrowDepositDisbursementsRelatedToPropertyAcquisition1_648be4df-ebe0-4a9b-94dd-a9ea9ddc4794" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/NetIncomePerShareScheduleofReconciliationofNetIncomeandNumberofSharesintheCalculationofBasicandDilutedNetIncomeperShareDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#NetIncomePerShareScheduleofReconciliationofNetIncomeandNumberofSharesintheCalculationofBasicandDilutedNetIncomeperShareDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/NetIncomePerShareScheduleofReconciliationofNetIncomeandNumberofSharesintheCalculationofBasicandDilutedNetIncomeperShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_a32e4fed-39a0-4ee0-9460-457977138826" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_90994eaf-bfb3-43f2-8e9d-e18974b6edbd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_a32e4fed-39a0-4ee0-9460-457977138826" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_90994eaf-bfb3-43f2-8e9d-e18974b6edbd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7e5b6eb3-a703-4328-bc25-d8cd9d03130c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_90994eaf-bfb3-43f2-8e9d-e18974b6edbd" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7e5b6eb3-a703-4328-bc25-d8cd9d03130c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_7e5b6eb3-a703-4328-bc25-d8cd9d03130c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7e5b6eb3-a703-4328-bc25-d8cd9d03130c" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_7e5b6eb3-a703-4328-bc25-d8cd9d03130c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_ae0bb6da-f3c1-48f9-9973-91347269a652" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7e5b6eb3-a703-4328-bc25-d8cd9d03130c" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_ae0bb6da-f3c1-48f9-9973-91347269a652" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_cc4d72c6-d71e-469d-a60f-bd0bbbcc1a84" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_ae0bb6da-f3c1-48f9-9973-91347269a652" xlink:to="loc_us-gaap_EmployeeStockOptionMember_cc4d72c6-d71e-469d-a60f-bd0bbbcc1a84" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_9c6bf398-b378-4812-8a8f-8ae2d58a618b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_ae0bb6da-f3c1-48f9-9973-91347269a652" xlink:to="loc_us-gaap_EmployeeStockMember_9c6bf398-b378-4812-8a8f-8ae2d58a618b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_78fe7788-cc2b-4a6f-9b28-21a17213d480" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_ae0bb6da-f3c1-48f9-9973-91347269a652" xlink:to="loc_us-gaap_WarrantMember_78fe7788-cc2b-4a6f-9b28-21a17213d480" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_63fb31e4-84f4-4919-89d3-6d0b39583e54" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_ae0bb6da-f3c1-48f9-9973-91347269a652" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_63fb31e4-84f4-4919-89d3-6d0b39583e54" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_80b3b50b-4157-4114-b426-4b26e15b97b0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_a32e4fed-39a0-4ee0-9460-457977138826" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_80b3b50b-4157-4114-b426-4b26e15b97b0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_a6b4caa9-8050-466f-a8a0-7b390635ea32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_80b3b50b-4157-4114-b426-4b26e15b97b0" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_a6b4caa9-8050-466f-a8a0-7b390635ea32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_4eda8f8b-b694-42e7-b19f-f7460073aa0d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_a32e4fed-39a0-4ee0-9460-457977138826" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_4eda8f8b-b694-42e7-b19f-f7460073aa0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_1e2203b6-78b2-47b1-aa04-4411dcff1134" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_4eda8f8b-b694-42e7-b19f-f7460073aa0d" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_1e2203b6-78b2-47b1-aa04-4411dcff1134" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_905f818d-43de-4526-9531-8a83a784341a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_4eda8f8b-b694-42e7-b19f-f7460073aa0d" xlink:to="loc_us-gaap_EarningsPerShareBasic_905f818d-43de-4526-9531-8a83a784341a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDilutedAbstract_7844cf4c-78fb-4371-9267-352399544dc7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDilutedAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_a32e4fed-39a0-4ee0-9460-457977138826" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDilutedAbstract_7844cf4c-78fb-4371-9267-352399544dc7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_ad3c9169-ec73-451e-b940-4d65de3c092f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDilutedAbstract_7844cf4c-78fb-4371-9267-352399544dc7" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_ad3c9169-ec73-451e-b940-4d65de3c092f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_8a074776-430d-4cb9-8e30-96370a0833e0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_a32e4fed-39a0-4ee0-9460-457977138826" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_8a074776-430d-4cb9-8e30-96370a0833e0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_83a21cf4-ba49-4253-a758-0711c2724b10" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_5ba838cc-123b-4f0c-9e64-20836335b345" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_8a074776-430d-4cb9-8e30-96370a0833e0" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_5ba838cc-123b-4f0c-9e64-20836335b345" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_247dcbc5-aab7-415f-bd73-ecc385e93dd8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_8a074776-430d-4cb9-8e30-96370a0833e0" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_247dcbc5-aab7-415f-bd73-ecc385e93dd8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_4abcdc1a-f33b-4b14-a197-508ffcc4af8c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_8a074776-430d-4cb9-8e30-96370a0833e0" xlink:to="loc_us-gaap_EarningsPerShareDiluted_4abcdc1a-f33b-4b14-a197-508ffcc4af8c" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/NetIncomePerShareScheduleofPotentiallyDilutiveSecuritiesDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#NetIncomePerShareScheduleofPotentiallyDilutiveSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/NetIncomePerShareScheduleofPotentiallyDilutiveSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_d74273a9-8f74-4381-ac93-db0f1dc846ac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_24be7461-a569-47e1-80b5-e1d3fdec73f0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_d74273a9-8f74-4381-ac93-db0f1dc846ac" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_24be7461-a569-47e1-80b5-e1d3fdec73f0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7f1b84bd-c8dc-4e12-a8a9-5cf1c430cbd0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_24be7461-a569-47e1-80b5-e1d3fdec73f0" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7f1b84bd-c8dc-4e12-a8a9-5cf1c430cbd0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_7f1b84bd-c8dc-4e12-a8a9-5cf1c430cbd0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7f1b84bd-c8dc-4e12-a8a9-5cf1c430cbd0" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_7f1b84bd-c8dc-4e12-a8a9-5cf1c430cbd0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_c8999345-f74f-40e2-a882-19530decce8b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_7f1b84bd-c8dc-4e12-a8a9-5cf1c430cbd0" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_c8999345-f74f-40e2-a882-19530decce8b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_fbcdeba1-ff27-463d-814a-31753c0e9d7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_c8999345-f74f-40e2-a882-19530decce8b" xlink:to="loc_us-gaap_EmployeeStockOptionMember_fbcdeba1-ff27-463d-814a-31753c0e9d7e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_e7205f26-017d-49bc-80bf-9353b657a6e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_c8999345-f74f-40e2-a882-19530decce8b" xlink:to="loc_us-gaap_EmployeeStockMember_e7205f26-017d-49bc-80bf-9353b657a6e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_0adde895-1f1f-4e4d-947b-62b043f3d4fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_c8999345-f74f-40e2-a882-19530decce8b" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_0adde895-1f1f-4e4d-947b-62b043f3d4fb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_b0e518df-83a0-46b8-8377-bfe06a2b0726" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_d74273a9-8f74-4381-ac93-db0f1dc846ac" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_b0e518df-83a0-46b8-8377-bfe06a2b0726" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/SegmentsSummaryofNetIncometoAllocateResourceDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#SegmentsSummaryofNetIncometoAllocateResourceDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/SegmentsSummaryofNetIncometoAllocateResourceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_21fc2d6a-0c72-421f-aeac-3f14a04fdc32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_21fc2d6a-0c72-421f-aeac-3f14a04fdc32" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_c45a728a-cf4b-43e0-8a80-c27d7963942e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_21fc2d6a-0c72-421f-aeac-3f14a04fdc32" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_c45a728a-cf4b-43e0-8a80-c27d7963942e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_c45a728a-cf4b-43e0-8a80-c27d7963942e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_c45a728a-cf4b-43e0-8a80-c27d7963942e" xlink:to="loc_us-gaap_SegmentDomain_c45a728a-cf4b-43e0-8a80-c27d7963942e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_fee425df-06fd-449c-91d0-0dbeaecd3d98" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_c45a728a-cf4b-43e0-8a80-c27d7963942e" xlink:to="loc_us-gaap_SegmentDomain_fee425df-06fd-449c-91d0-0dbeaecd3d98" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_ReportableSegmentMember_ee228ed4-4b45-4ee9-995a-a4534249c439" xlink:href="pgny-20250630.xsd#pgny_ReportableSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_fee425df-06fd-449c-91d0-0dbeaecd3d98" xlink:to="loc_pgny_ReportableSegmentMember_ee228ed4-4b45-4ee9-995a-a4534249c439" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_0cd8b1ce-ed4b-4301-88f8-409ef0f85c8b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_0cd8b1ce-ed4b-4301-88f8-409ef0f85c8b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_aee9159b-7de9-4f27-80e4-e9be3e3ba85a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_aee9159b-7de9-4f27-80e4-e9be3e3ba85a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_SalesAndMarketing_b193a840-f489-406b-b2f9-0755e5e8ce45" xlink:href="pgny-20250630.xsd#pgny_SalesAndMarketing"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_pgny_SalesAndMarketing_b193a840-f489-406b-b2f9-0755e5e8ce45" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_abf21676-9312-42c0-85b0-547901ce83cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_abf21676-9312-42c0-85b0-547901ce83cb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOther_bfb442b2-8901-4509-8c03-60fd30956ad7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_InterestIncomeOther_bfb442b2-8901-4509-8c03-60fd30956ad7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_52e6a978-706f-492e-815d-91d4a3cabba7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_52e6a978-706f-492e-815d-91d4a3cabba7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_387a487a-6eb9-42cd-a2e1-e04b615545e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_387a487a-6eb9-42cd-a2e1-e04b615545e8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_3036cc3c-88d2-476c-a74b-5d6f75ac01ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_4082f9ba-645a-46ad-86dd-bcb5ca9daead" xlink:to="loc_us-gaap_Assets_3036cc3c-88d2-476c-a74b-5d6f75ac01ab" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://progyny.com/role/SubsequentEventsDetails" xlink:type="simple" xlink:href="pgny-20250630.xsd#SubsequentEventsDetails"/>
  <link:definitionLink xlink:role="http://progyny.com/role/SubsequentEventsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtLineItems_33add009-4a00-423d-9d69-1889411a275e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShortTermDebtTable_295c3a2c-da7f-4739-af01-79217e859ec1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShortTermDebtTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShortTermDebtLineItems_33add009-4a00-423d-9d69-1889411a275e" xlink:to="loc_us-gaap_ScheduleOfShortTermDebtTable_295c3a2c-da7f-4739-af01-79217e859ec1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_9b383309-7a93-4cfc-995c-59f5229d873b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShortTermDebtTable_295c3a2c-da7f-4739-af01-79217e859ec1" xlink:to="loc_us-gaap_DebtInstrumentAxis_9b383309-7a93-4cfc-995c-59f5229d873b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_9b383309-7a93-4cfc-995c-59f5229d873b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_9b383309-7a93-4cfc-995c-59f5229d873b" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_9b383309-7a93-4cfc-995c-59f5229d873b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1364bf2d-6783-43a9-af3e-da862361afd3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_9b383309-7a93-4cfc-995c-59f5229d873b" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1364bf2d-6783-43a9-af3e-da862361afd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_CreditAgreementMember_57098be4-c3a9-4297-8c4c-7be5042bebda" xlink:href="pgny-20250630.xsd#pgny_CreditAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1364bf2d-6783-43a9-af3e-da862361afd3" xlink:to="loc_pgny_CreditAgreementMember_57098be4-c3a9-4297-8c4c-7be5042bebda" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_0b468b7f-89ca-4448-b8fd-c308db95b8de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShortTermDebtTable_295c3a2c-da7f-4739-af01-79217e859ec1" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_0b468b7f-89ca-4448-b8fd-c308db95b8de" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_0b468b7f-89ca-4448-b8fd-c308db95b8de_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_0b468b7f-89ca-4448-b8fd-c308db95b8de" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_0b468b7f-89ca-4448-b8fd-c308db95b8de_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_b68d6614-aacd-4b67-ab50-ea69b1a3cb1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_0b468b7f-89ca-4448-b8fd-c308db95b8de" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_b68d6614-aacd-4b67-ab50-ea69b1a3cb1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_a6e4954d-bed8-4ea2-8dba-4049c5a123e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_b68d6614-aacd-4b67-ab50-ea69b1a3cb1e" xlink:to="loc_us-gaap_SubsequentEventMember_a6e4954d-bed8-4ea2-8dba-4049c5a123e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_850a194e-f297-4c68-a3be-276f28e778ed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShortTermDebtTable_295c3a2c-da7f-4739-af01-79217e859ec1" xlink:to="loc_us-gaap_CreditFacilityAxis_850a194e-f297-4c68-a3be-276f28e778ed" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_850a194e-f297-4c68-a3be-276f28e778ed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_850a194e-f297-4c68-a3be-276f28e778ed" xlink:to="loc_us-gaap_CreditFacilityDomain_850a194e-f297-4c68-a3be-276f28e778ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_677417b4-359f-41ad-9c0a-fe97948ea12d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_850a194e-f297-4c68-a3be-276f28e778ed" xlink:to="loc_us-gaap_CreditFacilityDomain_677417b4-359f-41ad-9c0a-fe97948ea12d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_5f7c337a-aad7-4b8b-8d0a-338d3ff4f294" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_677417b4-359f-41ad-9c0a-fe97948ea12d" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_5f7c337a-aad7-4b8b-8d0a-338d3ff4f294" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_12134cbf-041d-45f8-b79d-8d3fd2ff9082" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShortTermDebtTable_295c3a2c-da7f-4739-af01-79217e859ec1" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_12134cbf-041d-45f8-b79d-8d3fd2ff9082" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_12134cbf-041d-45f8-b79d-8d3fd2ff9082_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_12134cbf-041d-45f8-b79d-8d3fd2ff9082" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_12134cbf-041d-45f8-b79d-8d3fd2ff9082_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_2aca4a1e-c003-4734-aa84-1eb1d679f948" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_12134cbf-041d-45f8-b79d-8d3fd2ff9082" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_2aca4a1e-c003-4734-aa84-1eb1d679f948" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_f66f2817-fe19-44bd-81ab-b1f5a6627648" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_2aca4a1e-c003-4734-aa84-1eb1d679f948" xlink:to="loc_us-gaap_LineOfCreditMember_f66f2817-fe19-44bd-81ab-b1f5a6627648" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_de1d936e-b6a4-4ee8-a87f-f7a9d320a9f3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShortTermDebtLineItems_33add009-4a00-423d-9d69-1889411a275e" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_de1d936e-b6a4-4ee8-a87f-f7a9d320a9f3" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd#eedm"/>
  <link:definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_AccruedLiabilitiesAndOtherLiabilitiesCurrent_b1cab9f1-d6d0-49c3-835d-1b90d8a9d4af" xlink:href="pgny-20250630.xsd#pgny_AccruedLiabilitiesAndOtherLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:to="loc_pgny_AccruedLiabilitiesAndOtherLiabilitiesCurrent_b1cab9f1-d6d0-49c3-835d-1b90d8a9d4af" xlink:type="arc" order="41"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#IndividualsOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllIndividualsMember" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_AllIndividualsMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_AllisonSwartzMember_2cc8d3b9-c2a8-4141-a1cc-eab656f9be0b" xlink:href="pgny-20250630.xsd#pgny_AllisonSwartzMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_pgny_AllisonSwartzMember_2cc8d3b9-c2a8-4141-a1cc-eab656f9be0b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_pgny_CherylScottMember_29465d41-cf86-41b5-9936-17bce64cafe1" xlink:href="pgny-20250630.xsd#pgny_CherylScottMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_pgny_CherylScottMember_29465d41-cf86-41b5-9936-17bce64cafe1" xlink:type="arc" order="3"/>
  </link:definitionLink>
</link:linkbase>
