Euploidy rates are comparable between progestin protocol ovarian stimulation and gonadotropin-releasing hormone antagonist protocol ovarian stimulation cycles

To compare blastocyst euploidy rates between progestin protocol ovarian stimulation and GnRH antagonist protocol ovarian stimulation cycles? Retrospective cohort study. Women undergoing assisted reproductive technology cycles with own oocytes. Ovarian stimulation was commenced on day 2 / 3 of the cycle and either GnRH-antagonist protocol was employed or progestin protocol with dydrogesterone at a dose of 30 mg/day in three divided doses was started on the same day with gonadotropins or the following day and continued until (including) the day of final oocyte maturation. Blastocyst euploidy rates. 4755 stimulation cycles were included in the study and 973 GnRH antagonist and 398 propensity score matched progestin protocol cycles were included in the analyses. In bivariate comparisons, mature oocyte yield, numbers of zygotes, blastocysts, euploid blastocysts, and euploidy rate per biopsied blastocyst were similar between the groups. Multivariable mixed-effects regression analyses adjusted for confounders showed similar oocyte count (IRR 0.96, 95% CI 0.89-1.03), mature oocyte count (IRR 0.95, 95% CI 0.87-1.03), blastocyst count (IRR 1.12, 95% CI 0.97-1.29) and euploid blastocyst count (IRR 1.08, 95% CI 0.86-1.36). Euploidy rate per biopsy was similar between progestin protocol and antagonist protocols, and no significant interaction was detected between the protocol and patient age. Twenty-nine individuals, who underwent two stimulation cycles, one with progestin protocol and another with GnRH antagonist, in any order, within the same calendar year had similar metaphase two oocyte yield, blastocyst count, and euploidy rate with both protocols. The present study provides reassurance about the newer progestin protocol by demonstrating similar euploidy rates of blastocysts with GnRH antagonist protocols.