{"paper_id":"5805dbb0-5a4e-46ad-b812-6817e2b84c07","body_text":"Zusammenfassung\nDie Vorbereitung des Endometriums für einen Kryo-ET (Embryotransfer nach Kryokonservierung) ist mit verschiedenen Protokollen möglich. Heute wird der Transfer im ovulatorischen Zyklus favorisiert, im natürlichen Zyklus, im modifizierten natürlichen Zyklus mit Ovulationsinduktion oder im niedrig stimulierten Zyklus. HRT(„hormone replacement therapy“)-Protokolle werden nur bei definitiver Anovulation empfohlen, da gehäuft Schwangerschaftskomplikationen nach Kryo-Embryotransfer ohne eigenes sekretorisch aktives Corpus luteum auftreten. Neuere Methoden, wie das NPP(„natural proliferative phase“)-Protokoll oder das PO(„programmed ovulatory“)-Zyklusprotokoll, erlauben ein niedrigfrequentes Monitoring bei gleicher Effektivität.\nAbstract\nThe preparation of a receptive endometrium prior to frozen embryo transfer (FET) can be achieved with different protocols. FETs in ovulatory cycles have become the method of choice, including natural cycles, modified natural cycles with ovulation induction, and mild stimulation protocols. Hormone replacement therapy (HRT) protocols are mostly restricted to cases with definite anovulation, since pregnancy complications like hypertension and pre-eclampsia are more frequent after FET without a secretory corpus luteum. New methods like the natural proliferative phase (NPP) protocol or the programmed ovulatory (PO) cycle protocol allow for less frequent monitoring with equal effectiveness.\nSimilar content being viewed by others\nLiteratur\nAlonso-Mayo C, Kohls G, Santos-Ribeiro S, Soares SR, Garcia-Velasco JA (2024) Modified natural cycle allows a window of 7 days for frozen embryo transfer planning. Reprod Biomed Online 49:103774\nAtkinson M, Crittenden J, Smith H, Sjoblom C (2021) Retrospective cohort study on preparation regimens for frozen embryo transfer. Reprod. 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Hum Reprod Update 29:634–654\nAuthor information\nAuthors and Affiliations\nCorresponding author\nEthics declarations\nInteressenkonflikt\nT. Strowitzki gibt an, dass kein Interessenkonflikt besteht.\nFür diesen Beitrag wurden von den Autor/-innen keine Studien an Menschen oder Tieren durchgeführt. Für die aufgeführten Studien gelten die jeweils dort angegebenen ethischen Richtlinien.\nAdditional information\nRedaktion\nKlaus Diedrich, Lübeck\nSebastian Findeklee, Göttingen\nHinweis des Verlags\nDer Verlag bleibt in Hinblick auf geografische Zuordnungen und Gebietsbezeichnungen in veröffentlichten Karten und Institutsadressen neutral.\nQR-Code scannen & Beitrag online lesen\nRights and permissions\nAbout this article\nCite this article\nStrowitzki, T. Endometriale Vorbereitung im Kryozyklus. Gynäkologie 58, 499–505 (2025). https://doi.org/10.1007/s00129-025-05350-1\nAccepted:\nPublished:\nVersion of record:\nIssue date:\nDOI: https://doi.org/10.1007/s00129-025-05350-1","source_license":"CC0","license_restricted":false}