Progestin-Primed Ovarian Stimulation with Dydrogesterone versus Medroxyprogesterone Acetate in Women with Polycystic Ovarian Syndrome for in vitro Fertilization: A Retrospective Cohort Study

Purpose: Dydrogesterone (DYG) is an alternative progestin in progestin-primed ovarian stimulation (PPOS) protocol with weaker pituitary suppression than medroxyprogesterone acetate (MPA) in normal ovulatory women. However, the endocrinological characteristics, oocyte retrieval and pregnancy outcomes of DYG application in polycystic ovarian syndrome (PCOS) patients undergoing in vitro fertilization (IVF) remain unclear. Patients and methods: This retrospective cohort study included 420 PCOS patients who underwent controlled ovarian stimulation with human menopausal gonadotropin (hMG) and DYG (n=105) or MPA (n=315) from January 2014 to December 2017. Baseline characteristics of the two groups were balanced with propensity score matching using the nearest-neighbor random matching algorithm in a ratio of 1:3. The primary outcome measure was the number of oocytes retrieved. Other main outcome measures included the number of viable embryos, incidence of premature luteinizing hormone (LH) surge and live birth rate per frozen-thawed embryo transfer (FET) cycle. Results: A similar number of oocytes was retrieved in the two protocols (16.1 +/- 6.5 vs 15.1 +/- 10.0, P=0.342). Patients in both groups achieved consistent LH suppression with no premature LH surge detected. In the DYG + hMG group, the mean LH levels were significantly higher than the MPA + hMG group on cycle day 9-11 and trigger day (all P<0.001), and the dose of hMG was significantly lower (1710.7 +/- 431.6 vs 1891.3 +/- 402.2 IU, P<0.001). No significant between-group differences were found in the number of viable embryos (5.3 +/- 3.1 vs 5.0 +/- 4.1, P=0.139) and live birth rate per FET cycle (43.5% vs 47.7%, P=0.383). None of the participants experienced moderate-to-severe ovarian hyperstimulation syndrome in either group. Conclusion: Our results showed that the application of DYG in PPOS protocol could achieve comparable oocyte retrieval and pregnancy outcomes to MPA, but significantly reduce the consumption of gonadotropins in PCOS women for IVF treatment.