The use of donated oocytes for IVF is highly successful and offers nearly 100 percent pregnancy rates after five treatment cycles, a Spanish team reports. José Remohí (Instituto Valenciano de Infertilidad, Valencia, Spain) and colleagues reviewed reproductive outcomes in a total of 10537 oocyte donation cycles performed at a university-affiliated infertility clinic between 1995 and 2005. Overall rates of pregnancy, implantation, clinical pregnancy, and miscarriage per embryo transfer were 54.9 percent, 27.0 percent, 50.3 percent, and 19.0 percent, respectively. Rates of twin and higher-multiple pregnancies were 39.0 percent and 6.0 percent, respectively. Over the study period, the mean number of embryos transferred fell from 3.6 to 1.9, and both implantation and ongoing pregnancy rates improved significantly.
"Pregnancy rates did not differ among different indications for oocyte donation, age groups, or origin of sperm used for oocyte insemination," the authors comment. Cumulative pregnancy rates were 87.0 percent after three cycles and 96.8 percent after five cycles, indicating that success does not diminish with consecutive attempts. The authors say that oocyte donation has the advantage of being effective independent of the cause of female infertility and severity of male infertility, and conclude that their IVF using oocyte donation is "highly successful."