A Randomized Clinical Trial Assessing the Effectiveness Of Intrauterine Insemination For Couples With an Isolated Cervical Factor

Abstract

To assess the effectiveness of intrauterine insemination (IUI) in cervical factor subfertility. The effectiveness of IUI is well established for male and unexplained subfertility. Data on IUI for cervical factor subfertility from five small clinical trials are conflicting. Randomized clinical trial. We performed a randomized clinical trial in 17 Fertility Centers in The Netherlands. Couples were eligible if they had a cervical factor, diagnosed by a well-timed, non-progressive post-coital test (PCT) with normal semen parameters and otherwise no factors that reduced fertility. These couples were randomly allocated between expectant management or IUI for six months. In the first three IUI cycles no controlled ovarian hyperstimulation (COH) was given. If these attempts failed subsequent IUI cycles were performed with COH. The primary endpoint was ongoing pregnancy within 6 months. The treatment effect was expressed as a relative risk and 95% confidence interval (CI). The analysis was performed according the intention to treat principle. We assumed a three times higher pregnancy rate in the couples treated with IUI. To detect this anticipated difference in ongoing pregnancy rates after 6 months, with an alpha of 5% and a power of 80%, 55 couples were required in each group. At present, 98 couples have been included (89%) and six months follow-up is available for 77 couples. In the expectant management group, 11 couples (31%) became pregnant of which 9 had an ongoing pregnancy (26%). In the IUI group, 18 couples (43%) became pregnant of which 16 had an ongoing pregnancy (38%). The relative risk of an ongoing pregnancy was 1.5 (95% CI 0.99 to 2.2). This trial suggest a beneficial effect of IUI in couples with an isolated cervical factor. This effect should be considered by those who plea against performance of the post-coital test.