Egg donor aneuploidy rates significantly differ between fertility centers


      To investigate if aneuploidy rates differ between fertility centers. Aneuploidy rates could differ due to differences in population age and infertility indication. However, any differences in aneuploidy rates between egg donor cycles are probably induced by differences in center-specific treatments.


      Aneuploidy rates in blastocysts from egg donation cycles from different fertility centers were compared.

      Materials and Methods

      616 Egg donor cycles (average age 25.8 years) underwent blastocyst biopsy for PGS at 20 fertility centers. Biopsied samples were analyzed at the same reference laboratory by array CGH. Ploidy data were examined using multiple logistic regression considering the mean incidence of euploidy per patient to see whether euploidy rates differed among centers. Each facility was compared against the mean incidence of euploidy for all facilities.


      Different centers had significantly different incidences of euploidy and these were independent of the number of biopsied embryos and donor age. Euploidy rates significantly deviated from the average of 65% (0.65±0.01) in 7 of the 20 centers included, ranging from 42% to 80%. Four centers had significantly lower euploidy rates (0.42±0.10, 0.47±0.07, 0.51±0.03, 0.51±0.07) and 3 significantly higher (0.77±0.02, 0.79 ±0.03, 0.80±0.02).


      Aneuploidy rates in egg donors vary significantly per center. The differences were not attributable to cohort size (blastocysts biopsied). This is the first study to investigate the question of center-dependent aneuploidy controlling for indication and patient population by taking into account only egg donor cycles. The reasons for the observed differences between centers can only be speculated but include any of the factors that are known to affect oocyte and embryo development, such as hormonal stimulation regimes, laboratory conditions, gamete and embryo manipulation methods, or environmental differences. Age is not considered to play a role here since young age is a pre-requisite to anonymous egg donation.