Superovulation with intrauterine insemination in the treatment of infertility: a possible alternative to gamete intrafallopian transfer and in vitro fertilization.
In vitro fertilization and embryo transfer (IVF-ET) and gamete intrafallopian transfer (GIFT) are used to treat intractable infertility in women with no distortion of the pelvic viscera, despite the lack of controlled trials demonstrating efficacy. The mechanism of any purportedly enhanced cycle fecundity in ovulatory women without significant distortion of the pelvic viscera is unclear, but both GIFT and IVF-ET increase the number of male and female gametes at the site of fertilization. Intrauterine insemination (IUI) during human menopausal gonadotropin (hMG)-stimulated superovulatory cycles has similar potential but does not require oocyte retrieval. To evaluate the possibility that simply increasing the number of gametes at the site of fertilization might account for pregnancies attributed to IVF-ET and GIFT, the authors retrospectively analyzed the outcome of couples undergoing IUI during hMG cycles between 1983 and 1986 in women with normal pelvic anatomy. IUI during hMG-stimulated cycles yielded a cycle fecundity (f) of 0.17 for endometriosis, 0.29 for cervical factor, and 0.19 for idiopathic infertility, which approaches the fecundity of normal women and equals or exceeds that reported for IVF-ET and GIFT. The authors conclude that treatment with IUI in hMG cycles, alleviating the need for invasive oocyte retrieval, should be considered for inclusion in a randomized, controlled trial in comparison with IVF-ET and GIFT.