Background. Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women and is associated with the reproductive and metabolic disorders.

Objectives. To compare the ovulation and conception rates after the treatment with Clomiphene Citrate (CC) alone and in combination with metformin in infertile patients presented with polycystic ovarian syndrome (PCOS).

Material & Methods. This randomized controlled trial of independent cases and controls was conducted in the Department of Obstetrics and Gynecology, Hera General Hospital, Makkah, Saudi Arabia, during 2008. The 42 subjects diagnosed as PCOS were divided into group A and B (21 subjects in each) for the management with CC + metformin and CC alone, respectively. Group A received 500mg of metformin continuously, three times a day from the first cycle, for 6 months or until the pregnancy was confirmed. In both groups, CC was started with a dose of 50 mg from day-2 until day-6 of the menstrual cycle. The dose of CC was increased to 100 mg in the second and 150 mg in the third cycle, and then 150 mg remained for the rest of three cycles. With ovulation, the dose of CC was unaltered in both groups. Data were analyzed by using SPSS version 16.

Results. More than 50% of the females in both groups had a body mass index of >25. Group A achieved a higher rate of regular cycles, ovulation success, and conception than group B (71.4% vs. 38.1%; p=0.03), (76.2% vs. 38.1%; p=0.021) and (66.6% vs. 28.6%, p=0.01), respectively.

Conclusion. Management with metformin + CC increased the ovulation and conception rates.