Effects of metformin and clomiphene citrate on ovarian vascularity in patients with polycystic ovary syndrome

OBJECTIVE: To evaluate the effects of metformin and of clomiphene citrate (CC) on the ovarian blood perfusion and on perifollicular and peri-corpus luteum (CL) vascularity in anovulatory women with polycystic ovary syndrome (PCOS). DESIGN: Prospective cohort study. SETTING: University "Magna Graecia" of Catanzaro. PATIENT(S): Forty anovulatory nonobese patients with PCOS who ovulated under treatment with metformin (850 mg twice daily) plus placebo (metformin group) and 38 under placebo plus CC (150 mg for 5 days; CC group). Another 30 healthy normal cycled women (control group). INTERVENTION(S): Serial transvaginal ultrasonographic examinations. MAIN OUTCOME MEASURE(S): Ovary artery blood flow impedance, dimensions, and vascularization of the dominant follicle and of the CL. RESULT(S): No difference was observed in all parameters in metformin ovulating cycles in comparison with healthy controls. In CC ovulating cycles, ovarian artery impedance, and perifollicular and peri-CL vascularization the results were significantly different from the metformin and control groups. After grouping the stimulated cycles for reproductive outcomes, perifollicular vascularization alone ended up being significantly lower only in CC-stimulated cycles with unfavorable outcome. CONCLUSION(S): In patients with PCOS who ovulate under treatment with metformin, the ovarian blood flows are similar to those observed in healthy women, whereas CC administration reduces the ovarian and, specifically, the perifollicular vascularization.