Elevated estradiol levels in frozen embryo transfer have different effects on pregnancy outcomes depending on the stage of transferred embryos.

ABSTRACT: Supplementation with estradiol (E₂) is routinely used in frozen embryo transfer (FET) cycles and embryo age plays an important role in conceiving. This study was to compare the effects of serum E₂ levels on pregnancy outcomes between cleavage- and blastocyst-stage FET cycles using hormone replacement therapy. A total of 776 FET cycles (669 couples) performed from January 2016 to December 2019 were included in the present retrospective cohort study. Regarding cleavage-stage embryo transfers, E₂ levels on progesterone initiation day were significantly lower in the ongoing pregnancy/live birth (OP/LB) group than in the non-OP/LB group (214.75 ± 173.47 vs. 253.20 ± 203.30 pg/ml; P = 0.023). In addition, there were downward trends in implantation, clinical pregn

SUBMITTER: Li Q 

PROVIDER: S-EPMC8980097 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature