The use of propensity score matching to assess the benefit of the endometrial receptivity analysis in frozen embryo transfers

Objective: To study the impact of the endometrial receptivity analysis (ERA) on live birth rates in frozen embryo transfer (FET) cycles. Design: Retrospective cohort study. Setting: A single, large, university-affiliated infertility practice. Patient(s): Autologous FET cycles between January 1, 2014, and June 30, 2019, were reviewed. Multiple covariates that impact outcomes were used for propensity score matching; 133 ERA patients were matched to 353 non-ERA patients. Patients were assigned to the ERA group if they had an ERA during treatment and underwent at least one "personalized'' FET based on the ERA recommendations. Intervention(s): No interventions administered. Main Outcome Measure(s): Live birth rates per cycle in the FET cycle after ERA compared with that of matched non-ERA patients. Result(s): The live birth rates for the ERA group, 49.62%, and the matched non-ERA group, 54.96%, (odds ratio 0.8074; 95% confidence interval, 0.5424-1.2018) were not significantly different, nor was a difference seen in subanalyses based on prior number of FETs or receptivity status. Conclusion(s): The ERA identifies a patient's putative window of implantation with the goal of improving synchrony with the embryo, thereby achieving higher live birth rates. This study used propensity score matching to control for multiple covariates in a heterogenous group of patients to compare live birth rates. There was no difference in the live birth rate in patients who underwent the ERA compared with that of those who did not. (C) 2021 by American Society for Reproductive Medicine.