The effect of intrauterine human chorionic gonadotropin flushing on live birth rate after vitrified-warmed embryo transfer in programmed cycles: a randomized clinical trial.

Purpose: To assess the influence of intrauterine human chorionic gonadotropin (hCG) before embryo transfer on the clinical pregnancy and live birth rates after vitrified-warmed embryo transfer (ET) in programmed cycles.

Methods: This study was a single-blind randomized clinical trial for eligible patients underwent frozen ET cycles with long-term hormonal GnRH agonist protocol for endometrial preparation. Immediately prior to ET, the women were randomly divided into three groups.