INS and polycystic ovary syndrome: Recent studies have revealed that inflammation and obesity are important factors in the pathophysiological basis of PCOS, while both hyperandrogenemia and IR have established key roles in its development.[4,11] In 1980, Burghen et al first proposed that IR is a major clinical characteristic of PCOS.[12] In the next several decades, several researches have confirmed that there is a close relationship between PCOS and IR.[13] Any abnormality in the insulin signaling pathway can lead to IR.