INS and polycystic ovary syndrome: Therefore, the main strengths of this study are 1) it’s prospective design with inclusion of newly diagnosed PCOS women prevents pharmacotherapy and other confounding variables such as age and sex; 2) the association between ZAG and IR is investigated by EHC, a gold standard for evaluating insulin sensitivity; 3) importantly, the predictive values of ZAG for IR, PCOS, IGT and MetS are evaluated.