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.