The fact that menstruation is not cleared for seven or eight days may be related to coitus during menstruation or just after menstruation, or it may be caused by endocrine abnormality, organic diseases and other reasons. 1. Menstruation or intercourse just after menstruation: during menstruation or intercourse just after menstruation, it is easy to lead to pelvic tissue congestion and edema, resulting in poor repair of the uterine lining, which may result in menstruation for seven or eight days. 2. Endocrine abnormalities: common in luteal atrophy or luteal insufficiency, etc., may cause menstruation seven or eight days. For example, due to luteal insufficiency, resulting in poor development of the corpus luteum in the process of formation, or early degeneration, resulting in delayed development of the uterine lining. 3. Organic diseases: endometrial hyperplasia, endometrial polyps, endometrial cancer, etc., which can cause the patient’s menstruation to remain unclean for seven or eight days, and may be accompanied by symptoms such as excessive menstruation. There may also be other causes of menstruation, so it is recommended to consult a doctor as soon as possible to confirm the cause of the disease and then give targeted treatment.