Subtle progesterone rise on the day of human chorionic gonadotropin administration is associated with lower live birth rates in women undergoing assisted reproductive technology: a retrospective study with 2,555 fresh embryo transfers.

Objective: To evaluate the association between serum P levels on the day of hCG administration and pregnancy outcome in women undergoing controlled ovarian hyperstimulation, prevention of premature ovulation by GnRH analogues, and fresh ET after 5 days of embryo culture.

Design: Retrospective, observational, cohort study.

Setting: Private IVF center.

Predictive value of early serum beta-hCG levels after single blastocyst transfer.

Objective: Analysis of serum beta-human chorionic gonadotropin (beta-hCG) levels on standardized days after oocyte retrieval (OR) following single blastocyst transfer to predict pregnancy outcome after assisted reproductive technology.

Design: Retrospective study.

Setting: Private fertility center.