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Comparison of Clinical Pregnancy Outcomes after Fresh and Frozen Embryo Transfer
Hui Yu1, Yuehong Zhang1, Mei Han1
1Department of Gynecology and Obstetrics, Tongzhou District Maternal and Child Health Hospital, Beijing City 101199, China.
Objectives:
To analyze the clinical outcomes of the patients who underwent fresh or frozen embryo transfer, as well as the neonatal outcomes.
Methods:
We conducted a retrospective analysis of women who underwent in vitro fertilization with fresh and frozen embryo transfer from January 2019 to January 2021. All of the included embryo transfers resulted in live births at ≥28 weeks of gestation. All of the patients were divided into two groups according to the assisted reproductive technique that was used (fresh embryo transfer group (n = 101) and frozen embryo transfer group (n = 125)). Both groups were divided into subgroups based on a maternal age of ≥35 years. Result(s). Between the two groups, only the cesarean section rate was higher in the frozen transfer group, while no differences were shown for other outcomes. There were significant differences in the gestational hypertension and postpartum hemorrhage rates based on the subgroup comparison. No significant differences were detected in the offspring.
Conclusions:
Comparing fresh and frozen embryo transfers did not reveal any significant superiority. Venerable age exerts an apparent influence on pregnancy complications. Frozen embryo transfer is not always the best choice.

