Does delayed implantation affect reproductive outcomes in assisted reproductive technology?

Does delayed implantation affect reproductive outcomes in assisted reproductive technology? | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Does delayed implantation affect reproductive outcomes in assisted reproductive technology? Jiongjiong Tu, Meiyi Wangchen, Fei Gong This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4671118/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background To investigate whether delayed implantation affect reproductive outcomes in assisted reproductive technology (ART). Methods This is a single-centre retrospective cohort study. All frozen-thawed cylces were performed between February 2022 to January 2024. Serum hCG levels were sequentially tested on blastocyte transfer day 6, 8, 10 and 12. Patients with initial serum hCG ≥ 5IU/L on transfer day 6 were recorded as the normal implantation and hCG ≥ 5IU/L detected on transfer day 8, 10 and 12 was recorded as the delayed implantation. The reproductive outcomes were compared between groups. The primary outcome was ongoing pregnancy rate, secondary outcomes were biochemical pregnancy rate, miscarriage rate and ectopic pregnancy rate. Results For patients with delayed implantation, the biochemical pregnancy rate was significantly higher in contrast to those with normal implantation (52.6% vs. 16.1%, P = 0.000).The early miscarriage rate was comparable between groups (5.3% vs. 9.9%, P = 0.345). The ectopic pregnancy rate was also higher in delayed implantation group ( 3.5% vs. 0.3%, P = 0.006). The ongoing pregnancy rate was significantly lower in delayed implantation group in contrast to normal implantation group (31.6% vs. 73.6%, P = 0.000). After multivariate logistic regression analyses, normal implantation group had increased odds of ongoing pregnancy compared to delayed implantation group (adjusted OR, 6.36; 95% CI, 3.46–11.70, P = 0.000). Conclusions The delayed implantation is strongly associated with higher incidence of biochemical pregnancy and ectopic pregnancy as well as decreased ongoing pregnancy rate. hCG level delayed implantation blastocyte transfer IVF outcome Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4671118","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":322681075,"identity":"143768f5-e8de-4475-a490-8e8f18aa10ff","order_by":0,"name":"Jiongjiong Tu","email":"","orcid":"","institution":"Reproductive \u0026 Genetic Hospital of CITIC-Xiangya","correspondingAuthor":false,"prefix":"","firstName":"Jiongjiong","middleName":"","lastName":"Tu","suffix":""},{"id":322681076,"identity":"d2601db5-03df-4312-b830-f7f9f1393d86","order_by":1,"name":"Meiyi Wangchen","email":"","orcid":"","institution":"Reproductive \u0026 Genetic Hospital of CITIC-Xiangya","correspondingAuthor":false,"prefix":"","firstName":"Meiyi","middleName":"","lastName":"Wangchen","suffix":""},{"id":322681077,"identity":"b0396ac5-e74c-4514-a954-5137ac645b5f","order_by":2,"name":"Fei Gong","email":"data:image/png;base64,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","orcid":"","institution":"Reproductive \u0026 Genetic Hospital of CITIC-Xiangya","correspondingAuthor":true,"prefix":"","firstName":"Fei","middleName":"","lastName":"Gong","suffix":""}],"badges":[],"createdAt":"2024-07-02 03:31:50","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4671118/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4671118/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":83356141,"identity":"8bf1e936-f214-4d85-97ec-8f783c78fd53","added_by":"auto","created_at":"2025-05-23 15:08:34","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":342794,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4671118/v1_covered_6f9b3bb7-1e13-4443-9913-2f90376cb4b8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Does delayed implantation affect reproductive outcomes in assisted reproductive technology?","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"hCG level, delayed implantation, blastocyte transfer, IVF outcome","lastPublishedDoi":"10.21203/rs.3.rs-4671118/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4671118/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo investigate whether delayed implantation affect reproductive outcomes in assisted reproductive technology (ART).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis is a single-centre retrospective cohort study. All frozen-thawed cylces were performed between February 2022 to January 2024. Serum hCG levels were sequentially tested on blastocyte transfer day 6, 8, 10 and 12. Patients with initial serum hCG ≥ 5IU/L on transfer day 6 were recorded as the normal implantation and hCG ≥ 5IU/L detected on transfer day 8, 10 and 12 was recorded as the delayed implantation. The reproductive outcomes were compared between groups. The primary outcome was ongoing pregnancy rate, secondary outcomes were biochemical pregnancy rate, miscarriage rate and ectopic pregnancy rate.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor patients with delayed implantation, the biochemical pregnancy rate was significantly higher in contrast to those with normal implantation (52.6% vs. 16.1%, P = 0.000).The early miscarriage rate was comparable between groups (5.3% vs. 9.9%, P = 0.345). The ectopic pregnancy rate was also higher in delayed implantation group ( 3.5% vs. 0.3%, P = 0.006). The ongoing pregnancy rate was significantly lower in delayed implantation group in contrast to normal implantation group (31.6% vs. 73.6%, P = 0.000). After multivariate logistic regression analyses, normal implantation group had increased odds of ongoing pregnancy compared to delayed implantation group (adjusted OR, 6.36; 95% CI, 3.46–11.70, P = 0.000).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe delayed implantation is strongly associated with higher incidence of biochemical pregnancy and ectopic pregnancy as well as decreased ongoing pregnancy rate.\u003c/p\u003e","manuscriptTitle":"Does delayed implantation affect reproductive outcomes in assisted reproductive technology?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-25 19:36:41","doi":"10.21203/rs.3.rs-4671118/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ba634415-71e9-4e69-973e-060321ead856","owner":[],"postedDate":"July 25th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-05-23T15:08:17+00:00","versionOfRecord":[],"versionCreatedAt":"2024-07-25 19:36:41","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4671118","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4671118","identity":"rs-4671118","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}