Peri-menopausal women who have normal menstrual flow but dark menstrual flow are not necessarily close to menopause, but may have endometritis, ovarian hypoperfusion, endocrine dysfunction and other causes. 1. Endometritis: If endometritis occurs in perimenopausal women, in addition to the symptoms of abdominal pain, the endometrium is not peeled off well, manifested as black menstrual blood, prolonged menstrual period, at this time should be anti-inflammatory treatment. 2. Ovarian hypoplasia: perimenopausal women have low ovarian function, reduced synthesis of estrogen and progesterone, poor endometrial stripping, menstrual blood remains in the vagina for a long time, and the color becomes black after oxidation. At this time, exogenous supplementation of estrogen and progesterone can be used to regulate the menstrual cycle and promote the complete stripping of the endometrium. 3. Endocrine dysfunction: If the patient has a history of staying up late and working hard for a long period of time, the endocrine function can be affected, resulting in abnormal hormone secretion, incomplete stripping of the endometrium and darkening of menstrual blood. At this time, we should adjust the work and rest, appropriate rest, according to the patient’s specific situation to supplement estrogen and progesterone. It is recommended that perimenopausal women with dark menstrual blood should consult a doctor in a timely manner for systematic examination and treatment under the guidance of a professional doctor.