Menopause is medically known as perimenopause. Perimenopausal menstruation twice a month may be caused by normal physiological factors or pathological factors such as cervical disease or endometrial disease. 1. Normal physiological factors: perimenopausal period is characterized by a gradual decline in ovarian function and unstable hormone levels in the female body, so irregular menstruation may occur, and two periods in a month may be normal. 2. Pathological factors: (1) Cervical diseases: Perimenopausal women who have two periods in a month may have abnormal vaginal bleeding caused by diseases such as cervicitis or cervical cancer. Cervicitis or cervical cancer often manifests as contact vaginal bleeding, and patients may experience vaginal bleeding after sexual intercourse or transvaginal manipulation. (2) Endometrial disease: Perimenopausal women who experience menstruation twice a month may also experience abnormal uterine bleeding caused by diseases such as endometritis or endometrial cancer, which appear as menstruation twice a month. There may be other reasons for perimenopausal women to have menstruation twice a month, so they should consult the doctor in time, complete the relevant examination, clarify the cause of the disease under the doctor’s guidance, and carry out targeted treatment.