Preimplantation adoption: establishing pregnancy using donated oocytes and spermatozoa

The experience of transferring embryos produced through in-vitro fertilization (IVF) utilizing donated oocytes and spermatozoa is described. Recipients (n = 28; aged 38-59 years) received oral micronized oestradiol and i.m. progesterone and were synchronized to donors undergoing ovarian stimulation. Reasons for selecting therapy included advanced reproductive age (> 42 years; n = 21) or hypergonadotrophic hypogonadism (n = 7), combined with severe male factor infertility in 23 couples. Five women were single and without partners. Oocytes were fertilized by cryopreserved spermatozoa designated for use by the recipient. Up to five embryos were transferred transcervically. Supernumerary embryos were cryopreserved. A total of 36 aspirations produced 15.6 +/- 7.3 oocytes per retrieval. In 10/36 cycles (27.8%), embryos were available for cryopreservation. Using fresh embryos, the overall pregnancy rate was 38.9% (14/36), clinical pregnancy rate 33.3% (12/36), and ongoing/delivered pregnancy rate 30.6% (11/36). Three ongoing pregnancies were later established by transferring cryopreserved embryos. Adjusting for these events, the per aspiration overall pregnancy rate per retrieval was 47.2%, clinical pregnancy rate 41.7%, and ongoing/delivered pregnancy rate 38.9%. Implantation rates per individual embryo transferred were 16.6% following fresh embryo transfer. A viable pregnancy was achieved by 14 of 28 women (50% cumulative pregnancy rate). We conclude that using donor oocytes and donor spermatozoa is efficacious and allows couples of whom both members suffer from severe gamete abnormalities and single functionally agonadal women an effective means of achieving pregnancy.