{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T07:27:45Z","timestamp":1792740465425,"version":"4.5.0"},"reference-count":34,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T00:00:00Z","timestamp":1777939200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Endocrinol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>To determine if endometrial preparation protocols for frozen embryo transfers (FET) impact clinical and neonatal outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      A monocentric cohort study including all first autologous FET cycles of a single blastocyst from January 1st, 2020 to September 30th, 2023. The primary endpoint was live birth (LBR). Secondary endpoints included hCG-positive pregnancy (&amp;gt; 100 IU\/l), ongoing pregnancy (OPR), miscarriage, birthweight and term. Outcomes were also analyzed by subgroup: Day 5\/Day 6 embryos. Among the 2982 FET cycles, 1507 (50.5%) were artificial cycles (AC) and 1475 (49.5%) were cycles with a\n                      <jats:italic>corpus luteum<\/jats:italic>\n                      (CLC). Univariate and multivariate analyses were performed using logistic regression models adjusting on age at transfer, age at oocyte retrieval, body mass index (BMI), indication and duration of infertility, IVF\/ICSI, AMH, embryo quality, ovulatory status and year of transfer.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Age at the time of transfer (35.3\n                      <jats:italic>vs.<\/jats:italic>\n                      36.0 years old) and age at oocyte retrieval (34.8\n                      <jats:italic>vs.<\/jats:italic>\n                      35.4 years old) were significantly lower in AC compared to CLC. After adjustment, CLC significantly increased LBR (aOR = 1.39 [1.12;1.73],\n                      <jats:italic>P<\/jats:italic>\n                      =\u00a00.003) and OPR (aOR = 1.39 [1.12;1.74],\n                      <jats:italic>P<\/jats:italic>\n                      =\u00a00.003) and significantly decreased miscarriage (aOR=0.63 [0.49;0.79],\n                      <jats:italic>P<\/jats:italic>\n                      =\u00a00.0001) compared to AC. In subgroup analyses, Day 5 embryos had significantly higher LBR, OPR, hCG-positive rates and lower miscarriage rates compared to Day 6 embryos. Term of birth did not differ between the two groups.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Our study pleads for a preferential use of CLC protocols for endometrial preparation for FET in ovulatory women.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fendo.2026.1808602","type":"journal-article","created":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T04:16:57Z","timestamp":1777954617000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Outcomes of frozen embryo transfers from a large monocentric cohort (2982 cycles): towards a preferential use of cycles with a corpus luteum for endometrial preparation"],"prefix":"10.3389","volume":"17","author":[{"given":"Julie","family":"Labrosse","sequence":"first","affiliation":[{"name":"Department of Reproductive Medicine, American Hospital of Paris","place":["Neuilly-sur-Seine, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emilie","family":"Haab","sequence":"additional","affiliation":[{"name":"Department of Reproductive Medicine, American Hospital of Paris","place":["Neuilly-sur-Seine, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frida","family":"Entezami","sequence":"additional","affiliation":[{"name":"Department of Reproductive Medicine, American Hospital of Paris","place":["Neuilly-sur-Seine, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nathalie","family":"Massin","sequence":"additional","affiliation":[{"name":"Department of Reproductive Medicine, American Hospital of Paris","place":["Neuilly-sur-Seine, France"]},{"name":"Reproductive Medicine Department, Intercommunal Hospital of Cr\u00e9teil","place":["Cr\u00e9teil, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,5]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1093\/hropen\/hoab026","article-title":"ART in Europe, 2017: results generated from European registries by ESHRE","volume":"2021","author":"Wyns","year":"2021","journal-title":"Hum Reprod Open"},{"key":"B2","doi-asserted-by":"publisher","first-page":"126.e1","DOI":"10.1016\/j.ajog.2019.03.010","article-title":"Neonatal and maternal outcome after frozen embryo transfer: increased risks in programmed cycles","volume":"221","author":"Ginstr\u00f6m Ernstad","year":"2019","journal-title":"Am J Obstet Gynecol"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/dez079","article-title":"Endometrial preparation methods for frozen-thawed embryo transfer are associated with altered risks of hypertensive disorders of pregnancy, placenta accreta, and gestational diabetes mellitus","volume":"34","author":"Saito","year":"2019","journal-title":"Hum Reprod"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1161\/HYPERTENSIONAHA.118.12043","article-title":"Increased preeclampsia risk and reduced aortic compliance with In vitro fertilization cycles in the absence of a corpus luteum","volume":"73","author":"von Versen-H\u00f6ynck","year":"2019","journal-title":"Hypertension"},{"key":"B5","doi-asserted-by":"publisher","first-page":"341","DOI":"10.1186\/s12884-021-03791-9","article-title":"Perinatal outcomes of neonates born from different endometrial preparation protocols after frozen embryo transfer: a retrospective cohort study","volume":"21","author":"Li","year":"2021","journal-title":"BMC Pregnancy Childbirth"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1093\/hropen\/hoac007","article-title":"Impact of endometrial preparation on early pregnancy loss and live birth rate after frozen embryo transfer: a large multicenter cohort study (14\u2013421 frozen cycles)","volume":"2022","author":"Vinsonneau","year":"2022","journal-title":"Hum Reprod Open"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.3389\/fendo.2023.1182148","article-title":"Higher risk of pre-eclampsia and other vascular disorders with artificial cycle for frozen-thawed embryo transfer compared to ovulatory cycle or to fresh embryo transfer following in vitro fertilization","volume":"14","author":"Epelboin","year":"2023","journal-title":"Front Endocrinol (Lausanne)"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1016\/j.rbmo.2023.01.006","article-title":"Fetal growth disorders following medically assisted reproduction: are they due to maternal context or techniques? 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