Oocyte donation: comparison between recipients from different age groups.

Oocyte donation was carried out in 87 patients in 141 replacement cycles. These patients received oocytes from 108 women undergoing assisted reproductive technology procedures at our centre. Standardized hormonal replacement therapy and in-vitro fertilization procedures were performed. We divided recipients into four groups according to their age (group A, 21-35 years; B, 36-40 years; C, 41-49 years; and D, 50-61 years). Oocytes donors were 21-35 years old, and equally spread across these different age groups. There were significant differences in the pregnancy and implantation rates according to the age of the recipients; which were 45% and 23% respectively in women 21-35 years old (group A) versus 23% and 10% in women 41-49 years old (group C). A comparison of data between oocyte donors and young recipients, with similar results in donors and young recipients, with pregnancy rates of 45% and 42% and implantation rates of 23% and 19.5% respectively. Statistically significant differences were found between donors and the older recipients, pregnancy rates being 43% versus 23%, and implantation rates 18% versus 10%. These data seem to demonstrate a lesser likelihood of pregnancy and implantation in older recipients because of increasing uterine age.