Decreased libido in a 45-year-old woman may be caused by physiological factors such as sexual disharmony, stress and fatigue, or it may be caused by perimenopausal syndrome, premature ovarian failure, and other diseases such as hyperprolactinemia. 1. Physiological factors: If a 45-year-old woman is dissatisfied with her sexual partner or her sex life is not satisfied, she will have a low libido. In addition, 45-year-old women with excessive mental stress or prolonged overwork will also have symptoms of low libido. 2. Perimenopausal syndrome: Perimenopausal syndrome may be caused by physiological ovarian failure, heredity, ovarian damage and other reasons. Patients will show low libido, prolonged menstrual cycle, hot flashes and night sweats, so 45-year-old women with perimenopausal syndrome will have symptoms of low libido. 3. Premature ovarian failure: Premature ovarian failure is considered to be caused by chromosomal abnormalities, abnormalities, autoimmune diseases and other factors. If a 45-year-old woman suffers from premature ovarian failure, she will experience scanty menstruation, amenorrhea, decreased libido, vaginal dryness and other symptoms. 4. Other: 45-year-old women with decreased libido may also be caused by factors such as hyperprolactinemia and hypothyroidism. If it is physiological factors that cause a 45-year-old woman to have a decreased sex drive, it can be left untreated. For diseases that cause a decrease in libido in a 45-year-old woman, it is necessary to consult a doctor in time.