Ovulation induction and intrauterine insemination in infertile women with polycystic ovary syndrome: a comparison of drugs

Abstract

Objective: To study the effectiveness of different ovulation induction protocols in infertile women with polycystic ovary syndrome (PCOS) undergoing intrauterine insemination (IUI). Design: Retrospective cohort study. Patients: Infertile women with PCOS undergoing IUI had ovulation induced with clomiphene citrate (CC), letrozole, or gonadotropins. Main Outcome Measure: Live birth and multiple pregnancy rates. Results: We performed 1068 IUI cycles in 765 couples. Live birth rates were comparable in CC-stimulated cycles (13.9%), letrozole-stimulated cycles (13.5%, OR 0.96 [95% CI, 0.63, 1.47]), and gonadotropins-stimulated cycles (13.2%, OR 0.94[95% CI, 0.62, 1.43]). Multiple pregnancy rates were 8.3%, 4.1% (OR 0.47 [95% CI, 0.09, 2.42]), and 3.3% (OR 0.34 [95% CI, 0.07, 1.95]) in CC, letrozole and gonadotropins stimulated cycles, respectively. Compared to CC, letrozole generated more often mono-follicular growth (75.9% versus 67.0%; OR 1.55 [95% CI, 1.11, 2.15]) but not more often after gonadotropins (72.9%, OR 1.17 [95% CI, 0.82, 1.66]. Cycles with multi-follicular growth did not result in statistically higher live birth rates than cycles with mono-follicular growth (15.8% vs. 12.7%, OR 1.29 [95% CI 0.89, 1.89]), but more often in multiple pregnancies (15.5% versus 0.8%, OR 22.4 [95% CI, 2.8, 181.6]). Conclusion: In women with PCOS undergoing stimulated IUI, CC, letrozole and gonadotropins were equally effective and safe. Since multi-follicular growth increased the multiple pregnancy rates without increasing the overall live birth rate, ovulation induction would strictly aim for mono-follicular growth. Since letrozole had the highest mono-follicular growth rate, we recommend this drug as the treatment of first choice in infertile women undergoing ovulation induction and IUI.