EFFICACY OF OOCYTES DONATED BY OLDER WOMEN IN AN OOCYTE DONATION PROGRAM

Population and insemination studies indicate that women experience dec lining fertility with ageing, The question therefore arises whether ol der women are suitable oocyte donors. This study addresses this issue by examining the relationship between oocyte donor age and clinical ou tcome in a large oocyte donation programme, We retrospectively reviewe d data from 458 consecutive oocyte donation cycles completed by 164 di fferent designated oocyte donors, Data were divided into two groups: g roup A, cycles with donors aged 21-30 years at the time of follicular aspiration (193 cycles, 88 donors); and group B, cycles with donors ag ed 31-40 years at the time of follicular aspiration (265 cycles, 86 do nors), Five donors, because of ageing during repetitive donations, con tributed data to groups A and B, In a given cycle, all oocytes for a r ecipient came from only one designated donor, Comparing the two donor groups, there was no difference in the amount of gonadotrophin used to achieve optimal stimulation; however, more oocytes were obtained from group A than group B donors (16.8 +/- 6.9 and 15.1 +/- 8.1 respective ly, P < 0.05), Similar percentages of oocytes were fertilized in each group, resulting in the transfer of comparable numbers of embryos (4.5 +/- 1.1 and 4.4 +/- 1.3 respectively), Comparable clinical pregnancy rates were achieved (group A, 36%; group B, 37%). The spontaneous abor tion rates were also similar (group A, 20%; group B, 12%), resulting i n comparable ongoing and delivered pregnancy rates per cycle (group A, 29%; group B, 32%) and per embryo transferred (group A, 6.4%; group B , 7.3%), In conclusion, women of proven fertility should not be exclud ed from donating oocytes simply because of their age, There exists a c ohort of fertile women who resist the decreasing fecundity and increas ing spontaneous abortion rates associated with ageing, With careful sc reening, many women of proven fertility can donate oocytes until the a ge of 40 years with an efficacy equal to that of younger women, Given the relative shortage of suitable oocyte donors, and increasing reques ts from recipients with previous donor oocyte babies to obtain oocytes from the same, now older, donor, the findings of this study are of pr actical clinical importance.