A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live births
BackgroundEndometrial thickness (EMT) has been confirmed to be associated with pregnancy outcomes after in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET), but studies on its relationship with neonatal outcomes are still limited. To our knowledge, this study is the...
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2025-05-01
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| author | Tian Ye Tian Ye Tian Ye Tian Ye Huijuan Kong Huijuan Kong Huijuan Kong Huijuan Kong Zhiqin Bu Zhiqin Bu Zhiqin Bu Zhiqin Bu Wenqian Fan Wenqian Fan Wenqian Fan Wenqian Fan Linqing Du Linqing Du Linqing Du Linqing Du Jing Li Jing Li Jing Li Jing Li Yihong Guo Yihong Guo Yihong Guo Yihong Guo |
| author_facet | Tian Ye Tian Ye Tian Ye Tian Ye Huijuan Kong Huijuan Kong Huijuan Kong Huijuan Kong Zhiqin Bu Zhiqin Bu Zhiqin Bu Zhiqin Bu Wenqian Fan Wenqian Fan Wenqian Fan Wenqian Fan Linqing Du Linqing Du Linqing Du Linqing Du Jing Li Jing Li Jing Li Jing Li Yihong Guo Yihong Guo Yihong Guo Yihong Guo |
| author_sort | Tian Ye |
| collection | DOAJ |
| description | BackgroundEndometrial thickness (EMT) has been confirmed to be associated with pregnancy outcomes after in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET), but studies on its relationship with neonatal outcomes are still limited. To our knowledge, this study is the first to investigate the relationship between EMT on the day of hCG trigger and the risk of preterm delivery (PTD) in populations undergoing cleavage-stage embryo transfer and blastocyst transfer, respectively.MethodsThis study was a retrospective cohort study that included singleton live birth cycles of women who underwent autologous IVF/ICSI-ET at the Reproductive Medicine Center of the First Affiliated Hospital of Zhengzhou University from January 2016 to December 2023. The main study outcome was PTD. The relationship between EMT and PTD was explored using logistic regression in different models. These models were adjusted for baseline characteristics, cycle treatment parameters and maternal pregnancy complications among populations undergoing cleavage-stage embryo and blastocyst transfer.ResultsIn both the unadjusted model and Model I, which was adjusted for baseline characteristics, compared with that in the EMT 7.5–12 mm group, the risk of PTD was significantly greater in the EMT < 7.5 mm group and significantly lower in the EMT ≥ 12 mm group (P < 0.05). In Model II, which was adjusted for all potential confounding factors, including pregnancy conditions, an EMT ≥ 12 mm retained its independent protective effect against PTD in both populations. In contrast, an EMT < 7.5 mm and PTD (OR 2.19; 95% CI, 0.82–5.88; P = 0.118) did not significantly correlated in the blastocyst transfer population. However, in patients undergoing cleavage-stage embryo transfer, an EMT < 7.5 mm remained an independent risk factor for PTD (OR 2.14; 95% CI, 1.09–4.21; P = 0.027).ConclusionsA thin endometrium on the day of hCG trigger is independently associated with an increased risk of PTD in patients undergoing cleavage-stage embryo transfer but not in those undergoing blastocyst transfer. In contrast, a thick endometrium significantly reduces the risk of PTD in both populations. |
| format | Article |
| id | doaj-art-3a264de8ffd247f88c8768bd7d7149fa |
| institution | DOAJ |
| issn | 1664-2392 |
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| publishDate | 2025-05-01 |
| publisher | Frontiers Media S.A. |
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| series | Frontiers in Endocrinology |
| spelling | doaj-art-3a264de8ffd247f88c8768bd7d7149fa2025-08-20T03:12:38ZengFrontiers Media S.A.Frontiers in Endocrinology1664-23922025-05-011610.3389/fendo.2025.15741231574123A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live birthsTian Ye0Tian Ye1Tian Ye2Tian Ye3Huijuan Kong4Huijuan Kong5Huijuan Kong6Huijuan Kong7Zhiqin Bu8Zhiqin Bu9Zhiqin Bu10Zhiqin Bu11Wenqian Fan12Wenqian Fan13Wenqian Fan14Wenqian Fan15Linqing Du16Linqing Du17Linqing Du18Linqing Du19Jing Li20Jing Li21Jing Li22Jing Li23Yihong Guo24Yihong Guo25Yihong Guo26Yihong Guo27Centre for Reproductive Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaCentre for Reproductive Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaCentre for Reproductive Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaCentre for Reproductive Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaCentre for Reproductive Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaCentre for Reproductive Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaCentre for Reproductive Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Provincial Obstetrical and Gynecological Diseases (Reproductive Medicine) Clinical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaHenan Engineering Laboratory of Preimplantation Genetic Diagnosis and Screening, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, ChinaBackgroundEndometrial thickness (EMT) has been confirmed to be associated with pregnancy outcomes after in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET), but studies on its relationship with neonatal outcomes are still limited. To our knowledge, this study is the first to investigate the relationship between EMT on the day of hCG trigger and the risk of preterm delivery (PTD) in populations undergoing cleavage-stage embryo transfer and blastocyst transfer, respectively.MethodsThis study was a retrospective cohort study that included singleton live birth cycles of women who underwent autologous IVF/ICSI-ET at the Reproductive Medicine Center of the First Affiliated Hospital of Zhengzhou University from January 2016 to December 2023. The main study outcome was PTD. The relationship between EMT and PTD was explored using logistic regression in different models. These models were adjusted for baseline characteristics, cycle treatment parameters and maternal pregnancy complications among populations undergoing cleavage-stage embryo and blastocyst transfer.ResultsIn both the unadjusted model and Model I, which was adjusted for baseline characteristics, compared with that in the EMT 7.5–12 mm group, the risk of PTD was significantly greater in the EMT < 7.5 mm group and significantly lower in the EMT ≥ 12 mm group (P < 0.05). In Model II, which was adjusted for all potential confounding factors, including pregnancy conditions, an EMT ≥ 12 mm retained its independent protective effect against PTD in both populations. In contrast, an EMT < 7.5 mm and PTD (OR 2.19; 95% CI, 0.82–5.88; P = 0.118) did not significantly correlated in the blastocyst transfer population. However, in patients undergoing cleavage-stage embryo transfer, an EMT < 7.5 mm remained an independent risk factor for PTD (OR 2.14; 95% CI, 1.09–4.21; P = 0.027).ConclusionsA thin endometrium on the day of hCG trigger is independently associated with an increased risk of PTD in patients undergoing cleavage-stage embryo transfer but not in those undergoing blastocyst transfer. In contrast, a thick endometrium significantly reduces the risk of PTD in both populations.https://www.frontiersin.org/articles/10.3389/fendo.2025.1574123/fullendometrial thicknesspreterm deliverycleavage-stage embryo transferblastocyst transferhCG trigger day |
| spellingShingle | Tian Ye Tian Ye Tian Ye Tian Ye Huijuan Kong Huijuan Kong Huijuan Kong Huijuan Kong Zhiqin Bu Zhiqin Bu Zhiqin Bu Zhiqin Bu Wenqian Fan Wenqian Fan Wenqian Fan Wenqian Fan Linqing Du Linqing Du Linqing Du Linqing Du Jing Li Jing Li Jing Li Jing Li Yihong Guo Yihong Guo Yihong Guo Yihong Guo A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live births Frontiers in Endocrinology endometrial thickness preterm delivery cleavage-stage embryo transfer blastocyst transfer hCG trigger day |
| title | A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live births |
| title_full | A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live births |
| title_fullStr | A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live births |
| title_full_unstemmed | A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live births |
| title_short | A thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer: a retrospective cohort study of 11,111 singleton live births |
| title_sort | thinner endometrium is associated with a greater risk of preterm delivery after fresh cleavage embryo transfer but not after blastocyst transfer a retrospective cohort study of 11 111 singleton live births |
| topic | endometrial thickness preterm delivery cleavage-stage embryo transfer blastocyst transfer hCG trigger day |
| url | https://www.frontiersin.org/articles/10.3389/fendo.2025.1574123/full |
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thinnerendometriumisassociatedwithagreaterriskofpretermdeliveryafterfreshcleavageembryotransferbutnotafterblastocysttransferaretrospectivecohortstudyof11111singletonlivebirths |