Objective: To compare the insulin indexes obtained from oral glucose tolerance (OGTT) in polycystic ovary syndrome (PCOS). Methods: Thirty-five PCOS women aged 18-35 years and 45 healthy control women were studied. Body mass index (BMI), waist circumference (WC), and waist-to-hip ratio were registered. According to BMI, women were categorized as lean (L:19-24.9), overweight (Ow:25-29.9) and obese (Ob:>30). Plasma glucose and insulin were measured at baseline and 30, 60 and 120 minutes after oral glucose load (75g). Homeostasis model assessment (HOMA IR ), quantitative insulin sensitivity check index (QUICKI) and insulin sensitivity index (ISI-MF) were calculated. Results: Both fasting glucose and 30 minutes post glucose were significantly higher in lean PCOS women as compared with controls (p<0.001). AUC-G did not show any significant difference between patients and controls. Fasting insulin was significantly higher only in lean PCOS women (p<0.01). AUC-I, increased significantly as a function of BMI increment in both study groups, although higher values were observed in