Clomiphene citrate versus metformin as first-line approach for the treatment of anovulation in infertile patients with polycystic ovary syndrome

Context: Clomiphene citrate ( CC) and metformin are two effective drugs used to induce ovulation in patients with polycystic ovary syndrome ( PCOS), even if it is still unclear which compound between them should be initially administered.Objective: The aim of the study was to compare in a clinical setting the efficacy of CC and metformin as first-line approaches for treating anovulation in infertile PCOS patients.Design: This study was a multicenter, nonrandomized, prospective, controlled study.Setting: The study was conducted at the Department of Obstetrics and Gynecology, Universities "Magna Graecia" of Catanzaro and "Federico II" of Naples, Italy.Patients: Patients included 80 infertile anovulatory patients with PCOS allocated in two body mass index- and age-matched groups ( experimental and control groups).Interventions: Six months of 1700 mg/d metformin treatment ( experimental group) or CC was administered using a traditional incremental-dose protocol ( control group). In both groups, patients who ovulated under treatment continued the therapy for a total of 6 months.Main Outcome Measures: Reproductive outcomes were measured.Results: Experimental and control groups were studied for a total of 204 and 169 cycles, respectively. No difference between the two groups was observed in ovulation ( 55.4 vs. 59.8%, respectively; P = 0.396), pregnancy ( 10.8 vs. 11.2%, respectively; P = 0.888), and abortion ( 19.5 vs. 26.3%, respectively; P = 0.530) rates. The cumulative pregnancy rate was not different between groups ( 62.9 vs. 48.6%, respectively; P = 0.225).Conclusion: A 6-month course of 1700 mg/d metformin treatment and CC administered in an escalation protocol are two effective first-line approaches for improving fertility in anovulatory PCOS women.