{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T21:09:25Z","timestamp":1790197765325,"version":"4.1.0"},"reference-count":31,"publisher":"Elsevier BV","issue":"2","license":[{"start":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T00:00:00Z","timestamp":1785542400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/tdm\/userlicense\/1.0\/"},{"start":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T00:00:00Z","timestamp":1785542400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/legal\/tdmrep-license"}],"content-domain":{"domain":["clinicalkey.com","clinicalkey.com.au","clinicalkey.es","clinicalkey.fr","clinicalkey.jp","fertstert.org","elsevier.com","sciencedirect.com"],"crossmark-restriction":true},"short-container-title":["Fertility and Sterility"],"published-print":{"date-parts":[[2026,8]]},"DOI":"10.1016\/j.fertnstert.2026.04.024","type":"journal-article","created":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T22:49:51Z","timestamp":1777762191000},"page":"360-368","update-policy":"https:\/\/doi.org\/10.1016\/elsevier_cm_policy","source":"Crossref","is-referenced-by-count":2,"title":["Natural cycle frozen embryo transfer reduces obstetric complications: an inverse probability of treatment-weighted analysis"],"prefix":"10.1016","volume":"126","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1730-6693","authenticated-orcid":false,"given":"Shuhei","family":"So","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nao","family":"Murabayashi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wakasa","family":"Yamaguchi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naomi","family":"Miyano","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Misa","family":"Namba","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fumiko","family":"Tawara","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"78","reference":[{"key":"10.1016\/j.fertnstert.2026.04.024_bib1","doi-asserted-by":"crossref","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 (14421 frozen cycles)","volume":"2022","author":"Vinsonneau","year":"2022","journal-title":"Hum Reprod Open"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib2","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1016\/j.ejogrb.2022.10.015","article-title":"Early pregnancy complications after frozen-thawed embryo transfer in different cycle regimens: a retrospective cohort study","volume":"279","author":"Pape","year":"2022","journal-title":"Eur J Obstet Gynecol Reprod Biol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib3","doi-asserted-by":"crossref","first-page":"1567","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":"10.1016\/j.fertnstert.2026.04.024_bib4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.placenta.2025.02.016","article-title":"Risk of preeclampsia and other pregnancy complications in frozen single euploid embryo transfers after natural versus artificial endometrial preparation: a truncated randomized controlled trial","volume":"163","author":"Bellver","year":"2025","journal-title":"Placenta"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib5","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pmed.1004630","article-title":"Natural cycle versus hormone replacement therapy as endometrial preparation in ovulatory women undergoing frozen-thawed embryo transfer: the compete open-label randomized controlled trial","volume":"22","author":"Liu","year":"2025","journal-title":"PLoS Med"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib6","article-title":"Endometrial preparation and maternal and obstetrical outcomes after frozen blastocyst transfer","volume":"2","author":"Takeshima","year":"2022","journal-title":"AJOG Glob Rep"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib7","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1016\/j.rbmo.2020.03.009","article-title":"Maternal and perinatal outcomes in programmed versus natural vitrified-warmed blastocyst transfer cycles","volume":"41","author":"Makhijani","year":"2020","journal-title":"Reprod Biomed Online"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib8","doi-asserted-by":"crossref","first-page":"573","DOI":"10.1016\/j.fertnstert.2021.09.033","article-title":"The impact of different cycle regimens on birthweight of singletons in frozen-thawed embryo transfer cycles of ovulatory women","volume":"117","author":"Zhou","year":"2022","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib9","doi-asserted-by":"crossref","first-page":"378","DOI":"10.1186\/s12884-022-04682-3","article-title":"Adverse obstetric and perinatal outcomes in 2333 singleton pregnancies conceived after different endometrial preparation protocols: a retrospective study in China","volume":"22","author":"Yang","year":"2022","journal-title":"BMC Pregnancy Childbirth"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib10","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1186\/s12958-022-01009-x","article-title":"The impact of different endometrial preparation protocols on obstetric and neonatal complications in frozen-thawed embryo transfer: a retrospective cohort study of 3,458 singleton deliveries","volume":"20","author":"Xu","year":"2022","journal-title":"Reprod Biol Endocrinol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib11","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1111\/1471-0528.17343","article-title":"Hormone replacement cycles are associated with a higher risk of hypertensive disorders: retrospective cohort study in singleton and twin pregnancies","volume":"130","author":"Pape","year":"2023","journal-title":"Br J Obstet Gynaecol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib12","doi-asserted-by":"crossref","first-page":"R267","DOI":"10.1152\/ajpregu.00156.2011","article-title":"Maternal vasodilation in pregnancy: the emerging role of relaxin","volume":"301","author":"Conrad","year":"2011","journal-title":"Am J Physiol Regul Integr Comp Physiol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib13","doi-asserted-by":"crossref","first-page":"E677","DOI":"10.1152\/ajpendo.00225.2019","article-title":"Potential influence of the corpus luteum on circulating reproductive and volume regulatory hormones, angiogenic and immunoregulatory factors in pregnant women","volume":"317","author":"Conrad","year":"2019","journal-title":"Am J Physiol Endocrinol Metab"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib14","doi-asserted-by":"crossref","first-page":"412","DOI":"10.1177\/1933719118776792","article-title":"Effect of mode of conception on maternal serum relaxin, creatinine, and sodium concentrations in an infertile population","volume":"26","author":"von Versen-H\u00f6ynck","year":"2019","journal-title":"Reprod Sci"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib15","doi-asserted-by":"crossref","first-page":"873","DOI":"10.1016\/S0021-9258(18)49231-9","article-title":"Effects of estradiol on the metabolism of human placenta in vitro","volume":"205","author":"Villee","year":"1953","journal-title":"J Biol Chem"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib16","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1002\/ijgo.12761","article-title":"FIGO classification for the clinical diagnosis of placenta accreta spectrum disorders","volume":"146","author":"Jauniaux","year":"2019","journal-title":"Int J Gynaecol Obstet"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib17","first-page":"1271","article-title":"[Introduction of new birth size standards by gestational age]","volume":"114","author":"Itabashi","year":"2010","journal-title":"Nihon Shonika Gakkai Zasshi"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib18","doi-asserted-by":"crossref","first-page":"1299","DOI":"10.1097\/AOG.0b013e3181a45b25","article-title":"Hypertensive disorders and severe obstetric morbidity in the United States","volume":"113","author":"Kuklina","year":"2009","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib19","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1111\/1471-0528.16379","article-title":"Predicting risk of postpartum haemorrhage: a systematic review","volume":"128","author":"Neary","year":"2021","journal-title":"Br J Obstet Gynaecol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib20","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0318770","article-title":"Tone or tissue? A comparison of trends and risk factors of severe postpartum hemorrhage according to uterine atony or retained tissue in a hospital setting","volume":"20","author":"Pettersen","year":"2025","journal-title":"PLoS One"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib21","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1186\/s12884-023-06103-5","article-title":"Risk factors for postpartum haemorrhage in women with histologically verified placenta accreta spectrum disorders: a retrospective single-centre cross-sectional study","volume":"23","author":"Ghaem Maghami","year":"2023","journal-title":"BMC Pregnancy Childbirth"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib22","doi-asserted-by":"crossref","first-page":"184","DOI":"10.1016\/j.ejogrb.2020.12.018","article-title":"A Swedish register-based study exploring primary postpartum hemorrhage in 405 936 full term vaginal births between 2005 and 2015","volume":"258","author":"Thies-Lagergren","year":"2021","journal-title":"Eur J Obstet Gynecol Reprod Biol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib23","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1007\/s00404-021-06189-2","article-title":"Risk factors and clinical outcomes for placenta accreta spectrum with or without placenta previa","volume":"305","author":"Ogawa","year":"2022","journal-title":"Arch Gynecol Obstet"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib24","doi-asserted-by":"crossref","first-page":"458","DOI":"10.1097\/AOG.0000000000003970","article-title":"Placenta accreta spectrum without placenta previa","volume":"136","author":"Carusi","year":"2020","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib25","article-title":"Pathologically diagnosed placenta accreta spectrum without placenta previa: a systematic review and meta-analysis","volume":"5","author":"Sugai","year":"2023","journal-title":"Am J Obstet Gynecol MFM"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib26","doi-asserted-by":"crossref","first-page":"398","DOI":"10.1002\/rmb2.12343","article-title":"Impact of subchorionic hematoma in early pregnancy on obstetric complications: a retrospective cohort study in women who had live births after frozen-thawed embryo transfer","volume":"19","author":"So","year":"2020","journal-title":"Reprod Med Biol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib27","doi-asserted-by":"crossref","DOI":"10.1002\/rmb2.12592","article-title":"Risk factors for non-previa placenta accreta spectrum in pregnancies conceived through frozen embryo transfer during a hormone replacement cycle in Japan","volume":"23","author":"Matsuo","year":"2024","journal-title":"Reprod Med Biol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib28","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1016\/j.ejogrb.2024.02.040","article-title":"Risk factors for placenta accreta spectrum in pregnancies conceived after frozen-thawed embryo transfer in a hormone replacement cycle","volume":"296","author":"Fujita","year":"2024","journal-title":"Eur J Obstet Gynecol Reprod Biol"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib29","doi-asserted-by":"crossref","first-page":"1241","DOI":"10.1016\/j.fertnstert.2016.01.009","article-title":"Subchorionic hematomas are increased in early pregnancy in women taking low-dose aspirin","volume":"105","author":"Truong","year":"2016","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib30","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1016\/S0140-6736(24)00756-6","article-title":"Livebirth rate after one frozen embryo transfer in ovulatory women starting with natural, modified natural, or artificial endometrial preparation in Viet Nam: an open-label randomised controlled trial","volume":"404","author":"Ho","year":"2024","journal-title":"Lancet"},{"key":"10.1016\/j.fertnstert.2026.04.024_bib31","doi-asserted-by":"crossref","first-page":"1815","DOI":"10.1093\/humrep\/deaf149","article-title":"Endometrial preparation protocols for frozen embryo transfer: risk assessment and individualized management","volume":"40","author":"Polyzos","year":"2025","journal-title":"Hum Reprod"}],"container-title":["Fertility and Sterility"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0015028226002670?httpAccept=text\/xml","content-type":"text\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0015028226002670?httpAccept=text\/plain","content-type":"text\/plain","content-version":"vor","intended-application":"text-mining"}],"deposited":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T20:51:20Z","timestamp":1790196680000},"score":1,"resource":{"primary":{"URL":"https:\/\/linkinghub.elsevier.com\/retrieve\/pii\/S0015028226002670"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8]]},"references-count":31,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2026,8]]}},"alternative-id":["S0015028226002670"],"URL":"https:\/\/doi.org\/10.1016\/j.fertnstert.2026.04.024","relation":{},"ISSN":["0015-0282"],"issn-type":[{"value":"0015-0282","type":"print"}],"subject":[],"published":{"date-parts":[[2026,8]]},"assertion":[{"value":"Elsevier","name":"publisher","label":"This article is maintained by"},{"value":"Natural cycle frozen embryo transfer reduces obstetric complications: an inverse probability of treatment-weighted analysis","name":"articletitle","label":"Article Title"},{"value":"Fertility and Sterility","name":"journaltitle","label":"Journal Title"},{"value":"https:\/\/doi.org\/10.1016\/j.fertnstert.2026.04.024","name":"articlelink","label":"CrossRef DOI link to publisher maintained version"},{"value":"article","name":"content_type","label":"Content Type"},{"value":"\u00a92026 American Society for Reproductive Medicine, Published by Elsevier Inc.","name":"copyright","label":"Copyright"}]}}