Among the causes of ovulation disorders (group II of anovulation according to the World Health Organization classification), the dominant one is polycystic ovary syndrome (PCOS), and the remaining cases are classified as Hypothalamic-Pituitary-Ovarian Axis Dysfunction (HPOD). The exact etiology of both entities is unknown. To diagnose PCOS, the Rotterdam criteria must be met and other conditions that may cause hyperandrogenism or ovulation disorders must be excluded. PCOS is more often accompanied by other endocrine and metabolic disorders, such as obesity, dyslipidemia, hyperandrogenism, insulin resistance, diabetes, hyperprolactinemia and thyroid diseases, as well as infertility due to ovulation defect. These conditions not only significantly reduce quality of life (QoL), but also lead to an increased risk of cardiovascular disease, metabolic syndrome, adverse obstetric outcomes and an increased risk of endometrial cancer, further impairing QoL.