Background: Polycystic ovary syndrome (PCOS) is a heterogenous disorder and current proposed diagnostic criteria include a number of disorders with similar phenotypes but radically different etiologies. Menstrual irregularities are the most common finding among women with PCOS. The aim of this study to determine the effect of metformin on clinical features, metabolic, endocrine profile and insulin sensitivity in polycystic ovarian syndrome (PCOS) patients at newly established tertiary care center.