Analysis of donor heterogeneity as a factor affecting the clinical outcome of oocyte donation.

This study investigated factors that may affect the clinical outcome of oocyte donation on the basis of data from a clinical programme involving 243 treatment cycles analysed retrospectively. In each cohort, oocytes were distributed randomly to one, two or three recipients, which enabled the outcomes in terms of pregnancy and live birth rates to be compared among donors. The results were compared with respect to age of the donor and recipient, number of oocytes collected, fertilization and cleavage rates, qualitative embryo criteria (morphological grade) and other clinical criteria.