Hôpital Erasme - ULB, Fertility Clinic, Department of Obstetrics and Gynecology, Brussels, Belgium.
Centre for Big Data Research in Health, University of New South Wales, Sydney, NSW, Australia.
Gynecol Endocrinol. 2021 Jul;37(7):618-623. doi: 10.1080/09513590.2020.1827383. Epub 2020 Oct 5.
To assess the birthweight of neonates conceived after fresh and frozen embryo transfers (FET) and, if different, to investigate whether estradiol levels during the late follicular phase were associated with the observed difference.
Singleton pregnancies from fresh and FET transfers between January 1990 and December 2013 were compared retrospectively. A total of 2885 singleton pregnancies after fresh embryo transfer and 746 after FET were analyzed. Obstetric and neonatal outcomes were compared between fresh and FET cycles.
The singletons born after FET were found to have a significantly higher birth weight (3313 g), compared to those born after fresh embryo transfer (3143 g); p < .001. The main predictor of this difference was found to be estradiol levels at the end of the follicular phase. The difference in birthweight was inversely correlated to estradiol levels considering all cycles together but also considering fresh and frozen cycles separately.
Our study demonstrates a link between high estradiol levels and low birth weight of singletons after IVF both in fresh and frozen-thawed embryo transfer cycles. It provides additional support to the involvement of hyperestrogenemia in the process of implantation and on the subsequent fetal development.
评估新鲜胚胎移植（FET）和冷冻胚胎移植后新生儿的出生体重，如果不同，研究卵泡晚期雌二醇水平是否与观察到的差异有关。
回顾性比较 1990 年 1 月至 2013 年 12 月期间新鲜胚胎移植和 FET 的单胎妊娠。共分析了 2885 例新鲜胚胎移植后的单胎妊娠和 746 例 FET 后的单胎妊娠。比较新鲜和 FET 周期的产科和新生儿结局。
FET 后出生的单胎体重明显高于新鲜胚胎移植后出生的单胎体重（3313g）；p<.001。该差异的主要预测因素是卵泡晚期的雌二醇水平。综合所有周期以及新鲜和冷冻周期，均发现出生体重的差异与雌二醇水平呈负相关。
我们的研究表明，在新鲜胚胎移植和冷冻解冻胚胎移植周期中，IVF 后高雌二醇水平与单胎出生体重低之间存在联系。它为超雌激素血症在植入过程及其后续胎儿发育中的作用提供了额外的支持。
