Efficacy of Combined Cabergoline and Metformin Compared to Metformin Alone on Cycle Regularity in Patients with Polycystic Ovarian Disease with Hyperprolactinemia: A Randomized Clinical Trial.

PURPOSE: Polycystic ovarian syndrome (PCOS) is a common reproductive disorder. Increasing serum prolactin in these patients could be detected in both follicular and luteal phase of the normal and stimulated cycles. Hyperprolactinemia affects the hypothalamic-pituitary-ovarian axis causing anovulation and abnormal uterine bleeding. In this study, the efficacy of combined cabergoline and metformin therapy was compared to metformin therapy alone in patients with PCOS on the body mass index, androgen profile and menstrual cycle regulation.

METHODS: Two hundred and fifty patients with polycystic ovarian syndrome (PCOS) with increased serum prolactin were randomly allocated into two groups: group (1) received oral metformin tablet 1000 mg per day and cabergoline 0.5 g tablet weekly for 3 months as a case group, and group (2) received oral metformin tablet 1000 mg per day and a placebo tablet weekly for 3 months as the control group ( n  = 123). Body mass index (BMI), menstrual cycle regularity, serum testosterone, serum prolactin and dehydroepiandrosterone sulfate (DHEAS) level were compared before and after treatment in both groups.

RESULTS: There was significant decrease in body mass index and improvement of androgenic profile in both groups after treatment. In group (1), there was significant improvement in cycle regularity and significant decrease in serum prolactin level post-treatment.

CONCLUSIONS: The use of cabergoline in addition to metformin had more favorable effect on cycle regularity and prolactin level in patients with polycystic ovarian syndrome with hyperprolactinemia than the use of metformin alone.