Controlled ovarian hyperstimulation and intrauterine insemination for treatment of unexplained infertility should be limited to a maximum of three trials.

OBJECTIVE To investigate the optimum number of cycles of controlled ovarian hyperstimulation and intrauterine insemination in the treatment of unexplained infertility. DESIGN Observational prospective study. SETTING In vitro fertilization embryo transfer center. PATIENT(S) Five hundred ninety-four couples with unexplained infertility. INTERVENTION(S) Controlled ovarian hyperstimulation (COH), intrauterine insemination (IUI), in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI). MAIN OUTCOME MEASURE(S) Cycle fecundity. RESULT(S) One to 3 cycles of COH/IUI were performed in 594 patients (group A) undergoing 1,112 cycles (mean, 1.9 cycles/patient). Up to 3 further trials (cycles 4-6) of COH/IUI were then performed in 91 of these women (group B), a total of 161 cycles (mean, 1.8 cycles/patient). A historical comparison group C consisted of 131 patients with 3 failed cycles of COH/IUI who underwent 1 cycle of IVF and ICSI at our center. In group A, 182 pregnancies occurred, with a cycle fecundity of 16.4% and a cumulative pregnancy rate (PR) of 39.2% after the first 3 cycles. In group B, 9 pregnancies occurred in cycles 4-6, with a cycle fecundity of 5.6%, significantly lower than that of group A (P<.001). The cumulative PR rose to 48.5% by cycle 6, a further increase of only 9.3%. In the women undergoing IVF and ICSI in group C, 48 pregnancies occurred, with a cycle fecundity of 36.6% per cycle, significantly higher than that of group B (P<.001). CONCLUSION(S) In unexplained infertility, the cycle fecundity in the first three trials of COH and IUI was higher than in cycles 4-6, with a statistically significant difference. Patients should be offered IVF or ICSI if they fail to conceive after three trials of COH and IUI.