Controlled ovarian hyperstimulation (COH) parameters associated with donor euploidy rates

Abstract

The report that euploidy rates using donor oocytes vary among clinics led us to question what causes these differences in euploidy. We considered donors at one clinic that performed over 400 donor PGS cycles using the same embryology lab and the same genetics lab but in which there were significant differences of euploidy rates among the 6 different physicians who treated donors. Our goal was to identify differences in donor treatment that were associated with their different euploidy rates. Analysis of donor euploidy rates with reference to donor treatment parameters The fraction of embryos per donor cycle that were diagnosed as euploid (Euploidy rate) in egg donor cycles undergoing PGS (N = 423) were examined for associations with donor age, gonadotropin doses (dose/day, and the fraction of total gonadotropin provided by hMG = F(hMG)), days of stimulation, estradiol on day of trigger/mature oocytes retrieved, number of mature oocytes retrieved, number of embryos biopsied, incidence of euploidy and physician of record. Differences in parameters were examined using analysis of variance (ANOVA). The set of variables from the analysis was submitted to a principal component analysis. Euploidy rate was examined for associations with treatment parameters using pairwise post-hoc comparisons adjusting for multiple comparisons. Linear regression analysis was used to assess the relationships between the euploidy rate (dependent variable) and the treatment parameters. Euploidy rates and all examined treatment parameters varied significantly among treating physicians. Of these, euploidy rate was positively associated (p = 0.01) only with F(hMG) but not with the number of MII retrieved or other variables. On the other hand, the absolute number of euploid embryos was positively associated with MII retrieved. We have identified one variable associated with donor euploidy rates at this center (F(hMG)). Previous studies identified different rates of aneuploidy in similar groups of patients (egg donors) depending on the performing fertility center. In this study, restriction to one center minimized the effect on euploidy associated with different embryology laboratory treatments while emphasizing the differences attributed to different treating physicians. Further, the number of euploid embryos was associated with the number of MII oocytes retrieved. The universality of F(hMG)’s association with euploidy must be further investigated by examining data from other centers.