Comparable Outcomes Using Oral Dydrogesterone Vs. Micronized Vaginal Progesterone in Frozen Embryo Transfer: a Retrospective Cohort Study.

This retrospective study was conducted to determine whether using oral dydrogesterone (DYD) instead of micronized vaginal progesterone (MVP) in frozen embryo transfer (FET) cycles affects pregnancy outcomes. Women undergoing autologous FET in an academic fertility center were evaluated. Uses of 10 mg TID oral DYD or MVP for patients treated in FET cycles (artificial and ovulatory cycle, separately) were compared. The main outcome measure was live birth rates in each group. The study analyzed 599 cycles that occurred from January 2018 through December 2019. Chemical and clinical pregnancy rates were comparable between DYD vs. MVP groups (41.6% vs. 38.1%; P = 0.44 and 36.7% vs. 31.4%; P = 0.18, respectively). The ongoing pregnancy and delivery rates (29% vs. 22%, P = 0.06), as well as abortion rate (12.3% vs. 15.8%, P = 0.2), were comparable between the two groups. In a case-control sub-analysis of artificial FET cycles, we found comparable results between the two modes of luteal support. Similarly, results were comparable in ovulatory cycles using these medications for luteal support. Chemical and clinical pregnancy rates were comparable with DYD vs. MVP, in artificial FET (33.7% vs. 34.8%; P = 0.89 and 27.7% vs. 27.5%; P = 1), and in ovulatory FET (46.5% vs. 43.9%; P = 0.71 and 42.3% vs. 38.2%; P = 0.53), respectively. Our results indicate that in FET, pregnancy outcomes with oral DYD were not inferior to those with MVP.