Premature ovarian failure (POF), also known as primary ovarian insufficiency, is diagnosed in the event when primary or secondary amenorrhea and hypoestrogenism with high levels of gonadotropins occur in women before the age of 40. POF, caused by genetic, autoimmune and environmental factors, leads to a decrease in numbers of primordial follicles, accelerated atresia, and impaired follicular function. The diagnosis of POF is an indication for hormonal replacement therapy (HRT), which should be continued until the mean age of menopause in a given population. HRT reduces the intensity of vasomotor symptoms and has a beneficial effect on the central nervous, skeletal, cardiovascular, and urinary-reproductive systems.