Oocyte donation in Israel: a study of 1001 initiated treatment cycles.

There are numerous studies concerning pregnancy rates in oocyte donation, yet only a handful report the obstetric outcome in such pregnancies. The purpose of this study was to assess factors that influence pregnancy rates, to determine the incidence of complications, and to evaluate obstetric outcome in pregnancies resulting from oocyte donation. This study included 423 oocyte recipients who underwent 1001 oocyte donation cycles at the Oocyte Donation Programme, In-Vitro Fertilization (IVF)-Embryo Transfer Unit, Herzlia Medical Center, Israel. Donors were all healthy women < 34 years old who underwent IVF themselves. In 873 cycles, fertilization occurred and embryo transfer was performed, resulting in 194 clinical pregnancies. Pregnancy rates (PR) significantly declined with the increase in number of previous attempts, and with increasing age of recipient (36.8%/embryo transfer in patients < or = 30 compared to 17.8% in patients > 40 years old). A significant increment in PR was noted with the increasing number of embryos transferred. The overall PR was 22.2%/embryo transfer. However, in young amenorrhoeic patients with normal karyotypes undergoing their first cycle, PR was 52.2%; the 'take home baby' rate was 38.3% per patient undergoing embryo transfer and 17.8% per embryo transfer cycle. A significant increase in the incidence of pregnancy-induced hypertension and a higher proportion of abortions were noted in older patients. A significantly higher incidence of prematurity and low birthweight was observed in multiple pregnancies.