A prospective trial of intrauterine insemination of motile spermatozoa versus timed intercourse

STUDY OBJECTIVE: The efficacy of intrauterine insemination (IUI) of selected motile sperm. DESIGN: Prospective randomized sequential alternating cycle trial comparing IUI with luteinizing hormone (LH)-timed intercourse. SETTING: Clinical infertility service. PATIENTS: Couples selected included unexplained infertility (n = 73), cervical mucus hostility (n = 24), moderate semen defect (n = 110), and severe semen defect (n = 78). Two hundred eighty-five couples undertook 600 IUI cycles and 505 LH-timed intercourse. RESULTS: Overall, IUI was slightly more effective than LH-timed intercourse with a pregnancy rate of 6.2% versus 3.4% per cycle. When individual categories were considered only, IUI for severe semen defect was significantly better (5.6% versus 1.3%, P less than 0.05). The first IUI cycle was more effective when compared with both subsequent IUI cycles and the initial LH-timed cycle. Overall, 74% (27/37) of IUI pregnancies occurred in the first cycle. CONCLUSIONS: Compared with LH-timed intercourse, IUI provided little or no improved expectation of pregnancy but was beneficial in couples with severe semen defect. The occurrence of pregnancy was limited per cycle and confined essentially to the initial cycle of treatment. Continued IUI is considered to be unrewarding.