Work

Impact of orally and vaginally administered estradiol on live birth and neonatal outcomes in frozen-thawed embryo transfer cycles: A retrospective cohort study

Year: 2026

Type: article

Abstract: Objective: Previous studies have reported a higher rate of small for gestational age (SGA) newborns from fresh embryo transfers compared with frozen-thawed embryo transfers (FET), potentially due to the supraphysiologic serum estradiol levels observed during controlled ovarian stimulation. This study aimed to evaluate whether different regimens of exogenous estradiol administration influence live birth rates and neonatal outcomes in hormone replacement therapy (HRT)-FET cycles. Methods: We conducted a retrospective analysis of patients undergoing their first FET with HRT-based endometrial preparation between January 2015 and December 2018 at our center, comparing those who received estradiol both orally and vaginally (OVE group) with those who received estradiol orally only (OE group). Results: Patients in the OVE group achieved higher serum estradiol levels and underwent longer durations of estradiol treatment. No significant differences were found in live birth rate (adjusted odds ratio [OR], 1.327; 95% confidence interval [CI], 0.982 to 1.794; p=0.066) or clinical pregnancy rate (adjusted OR, 1.278; 95% CI, 0.937 to 1.743; p=0.121). The estradiol regimen did not affect singleton birth weight (β=-30.962; standard error=68.723; p=0.653), the odds of large for gestational age (adjusted OR, 1.165; 95% CI, 0.545 to 2.490; p=0.694), the odds of SGA (adjusted OR, 0.569; 95% CI, 0.096 to 3.369; p=0.535), or preterm delivery (adjusted OR, 0.969; 95% CI, 0.292 to 3.214; p=0.959). Conclusion: Combined oral and In subsequent cycles, patients received estrogen administration did not alter live birth rates or singleton neonatal outcomes, but was associated with higher serum estradiol levels and potential maternal risks.

Source: Daehan saengsik uihak hoeji/Clinical and experimental reproductive medicine

DOI: 10.5653/cerm.2025.07969

Authors: Yuan Liu, Jian Sun, Yanmei Hu, Yu Wu, Yixia Yang

Institutions: Shanghai Jiao Tong University, Shanghai First People's Hospital

Language: English

Topic: Assisted Reproductive Technology and Twin Pregnancy

Subfield: Pediatrics, Perinatology and Child Health

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: diamond

OpenAlex ID: W7118891310