INS and polycystic ovary syndrome: Although statin treatment improves insulin sensitivity22, 23 in patients with PCOS,12 increasing evidence shows that this therapy negatively affects glucose metabolism in hypercholesterolaemic patients with PCOS.24 Animal experiments showed that atorvastatin can reduce insulin sensitivity and impair glucose tolerance in rats.25 Furthermore, a human trial demonstrated increased insulin secretion after 6 weeks of statin therapy in women with PCOS.15 Our meta-analysis found that statins fail to improve F-INS and HOMA-IR in statins alone or in combination with metformin.