Comparison Of Progestin-Primed Ovarian Stimulation and GnRH Antagonist Protocols with Deltafolitropin Stimulation in Assisted Reproductive Technology: a Multicenter Trial

Objective: This study aimed to compare the efficacy of pituitary suppression with oral dydrogesterone (PPOS) versus GnRH antagonists in IVF/ICSI cycles undergoing preimplantation genetic testing for aneuploidy (PGT-A), with a focus on both laboratory and obstetric outcomes.Methods: This was a retrospective, multicenter, comparative cohort study conducted at five private fertility centers.A total of 372 IVF/ICSI cycles with PGT-A, performed between January and December 2023, were included without age restrictions.All patients underwent ovarian stimulation with fixed daily doses of follitropin delta (Rekovelle ® , Ferring Pharmaceuticals) and menotropin (Menopur ® , Ferring Pharmaceuticals), stratified by age group.Pituitary suppression was achieved using either a GnRH antagonist (cetrorelix acetate, Cetrotide ® , Merck) at 0.25 mg/day, initiated in a flexible regimen upon identification of a follicle ≥14 mm (n = 196), or dydrogesterone (DYG; Duphaston ® , Abbott) at 10 mg every 8 hours, initiated on day 1 of stimulation and continued until the end of the stimulation phase (n = 176).The primary outcome was live birth rate at the first embryo transfer.Analyses were performed using generalized linear models (GLM), with results expressed as odds ratios (OR) and 95% confidence intervals (CI).Analyses were adjusted for age, BMI, presence of endometriosis, and PCOS.Statistical analyses were performed using IBM SPSS Statistics, version 29.0 (2023).Results: Descriptive comparisons (table 1) using t-tests and chi-square tests showed no statistically significant differences between groups in baseline characteristics, including age (37.07±3.14 vs. 37.18 ± 3.37; p=0.733),BMI (24.04±3.67 .23.64±3.17;p=0.306),AMH levels (2.64±2.56 vs. 2.61±2.15;p=0.921), number of follicles ≥16 mm (8.69 ± 6.42 vs. 7.74 ± 5.31; p = 0.118), and total oocytes retrieved (13.51 ± 8.70 vs. 14.54±7.88;p=0.234).However, statistically significant differences were observed in stimulation duration (10.48±1.57vs. 9.85±1.20;p<0.001) and number of MII oocytes retrieved (10.33 ± 6.95 vs. 11.66 ± 6.10; p=0.050).While the live birth rate after the first embryo transfer was higher in the GnRH antagonist group, the difference did not reach statistical significance (50.51% vs. 41.47%;p=0.081).Despite a slight advantage in the studied outcome for the antagonist group, the GLM analysis showed no statistically significant difference between the groups.Conclusions: The present study found no statistically significant difference between the PPOS and antagonist protocols with respect to the clinical outcome of live birth after first embryo transfer.However, the number of MII oocytes retrieved in the DYG group was higher than the aGnRH.