IGFBP1 and Insulin resistance: Apart from chronic unopposed oestrogen exposure to the endometrium in women with PCOS, other potential molecular mechanisms which are thought to increase the risk of EC in women with PCOS include (i) insulin resistance and (ii) endometrial overexpression of insulin like growth factor-1 (IGF1), IGF binding protein-1 (IGFBP1), PTEN genes [6], sterol regulatory binding protein-1 (SREBP1) and adiponectin [7].