Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting women in their reproductive age, with significant reproductive, metabolic and psychological implications. The PCOS is a multifactorial disorder involving interactions between certain genes, environmental factors, gonadotropin dysfunction, insulin resistance (IR) and hyperandrogenism. Different phenotypes of PCOS exist, based on the PCOS definition by NIH and ESHRE/ARM and the clinical presentation. A large proportion of PCOS women have high luteinizing hormone (LH) levels. Partly due to the increased LH stimulation there is increased ovarian androgen production. The high androgen levels were suggested as the main cause of ovarian follicle maturation arrest with subsequent infertility. In addition, insulin stimulates and maintains ovarian androgen secretion, which explains the association between hyperinsulinemia and the severity of hirsutism in PCOS. There is no ideal therapy that treats all features of PCOS, so the treatment is directed towards the clinical presentation (targeted therapy).