Gonadotrophin ovarian stimulation and intrauterine insemination for unexplained infertility.

Over the past 15 years, there has been a marked increase in the use of ovulation induction and intrauterine insemination (IUI) for the treatment of unexplained infertility. However, although ovulation induction and IUI have rapidly gained popularity, clinical use is based largely on practical experience rather than on well-designed scientific studies. This article summarizes the evidence in this area. Despite clinical heterogeneity and different methodological qualities of the trials, it can be concluded that ovulation induction significantly improves the probability of conception in couples with unexplained infertility, particularly when associated with IUI. It is remarkable, though, that there has been only one large-scale, randomized trial of ovulation induction plus IUI in the treatment of unexplained infertility in which one of the study arms is an untreated control group. For couples requiring treatment, the complication rate must be minimized, particularly the occurrence of high-order multiple pregnancy. Evaluation of the effectiveness and safety of low-dose gonadotrophin administration in patients with unexplained infertility is limited and further studies are warranted.