Clomiphene citrate monitoring for intrauterine insemination timing: a randomized trial

Objective: To compare pregnancy rates with two different methods of intrauterine insemination (IUI) timing in patients treated with clomiphene citrate (CC). Design: Prospective, randomized trial. Setting: Academic medical center. Patient(s): One hundred fifty ovulatory, infertile women. Intervention(s): Patients were randomized into a luteinizing hormone (LH) Surge group or a follicle monitoring/human chorionic gonadotropin (hCG) group. All patients underwent baseline ultrasound. and took clomiphene citrate, during days 5-9. Patients in the LH surge group underwent IUI on the day after a home test for the LH surge was positive, whereas those in the hCG group received hCG according to ultrasound parameters and underwent insemination 33-40 hours later. Patients remained in the same study group for up to three cycles. Main Outcome Measure(s): Pregnancy rates per cycle and per patient. Result(s): No significant differences were found between groups in pregnancy rates per patient or per cycle. The LH surge group underwent IUI significantly later than the hCG group. Cancellation rates were significantly higher for the LH surge group (31% vs. 11%) and attributable mainly to failure to detect an LH surge. The majority of pregnancies in both treatment groups occurred in the first cycle. Conclusion(s): The decision to use hCG for IUI timing should be influenced by factors other than pregnancy rates.