A prospective randomized study of pregnancy rates following intrauterine and intracervical insemination using frozen donor sperm

Cryopreserved sperm have lowered fertility when compared with fresh sperm in artificial insemination by donor programs. The purpose of this study was to compare pregnancy rates following intrauterine insemination (IUI) and intracervical insemination (ICI) with cryopreserved sperm in a prospective trial using the patient as her own control. A total of 154 patients were randomized into alternating treatment cycles and underwent 238 cycles of IUI and 229 cycles of ICI. The pregnancy rate per treatment cycle was 9.7% following IUI and 3.9% following ICI. Treatment outcome was influenced by patient age, ovulatory status, and endometriosis. Pregnancy success correlated well with the post-thaw survival of sperm and the number of motile cells inseminated. In spite of having normal semen parameters, some donors were found to have markedly reduced sperm fecundity. We conclude that IUI with cryopreserved sperm can be an effective treatment for couples with infertility, genetic indications, or other reasons.