The aim of this study was to evaluate the effect of orlistat or metformin combined with Diane-35 on anthropometric, hormonal and metabolic parameters in overweight and obese polycystic ovary syndrome (PCOS) patients with insulin resistance (fasting insulin > 10 mIU/L). A total of 240 PCOS women were randomly allocated to orlistat plus Diane-35(OD group), metformin plus Diane-35(MD group), orlistat plus metformin plus Diane-35(OMD group) or Diane-35 (D group). Body weight, BMI, waist and hip circumference, blood pressure, endocrine profile, lipid profile and insulin resistance were assessed at baseline and after 3 months. Significant reductions in waist and hip circumference, serum LH, total testosterone and uric acid were observed in all groups compared with baseline. TG and TC significantly decreased in the OD group. Homeostasis model assessment insulin resistance (HOMA-IR) index was reduced in the OD (p = .015), MD (p = .001) and OMD (p = .004) groups. Body weight, BMI, systolic BP and HDL-C significantly changed in the OD and OMD group compared with the D group (p < .05). Side effects were less with orlistat than metformin. This study demonstrated that orlistat is more effective in reducing weight and lipid profile than metformin. Besides, orlistat has mild side-effects and is better tolerated compared with metformin.

Diane-35 in combination with orlistat or metformin is more effective in reducing androgen than Diane-35 alone. Orlistat is more effective in reducing body fat percentage than metformin. In addition, orlistat has mild side-effects and is better tolerated compared with metformin.