The eighth day of menstruation is still not clean may be a normal phenomenon, may also be caused by physiological factors (such as menopausal endometrial hyperplasia) or organic diseases (such as endometrial polyps or endometrial cancer, etc.), it is recommended to go to the hospital in a timely manner for examination and treatment in accordance with the doctor’s instructions. If the menstruation period is not clean for 8 days, it belongs to prolonged menstruation. The normal menstruation period of a woman should be 3~7 days, if the menstruation period is not clean for more than 7 days, it is called prolonged menstruation, and the reasons for prolonged menstruation are as follows: 1. Normal phenomenon: if it is regular each time the menstruation is within 8~10 days, it can be cleaned by itself, most of them don’t have too many problems. 2. Physiological factors: For example, when a woman is in puberty, the hypothalamus-pituitary-ovarian axis is not perfect for the regulation of menstruation, which can lead to prolonged menstrual periods. As for menopausal women, due to the decline of ovarian function, fluctuation of hormone level secreted by the ovaries, no ovulation or less ovulation, the endometrium is stimulated by a single estrogen causing endometrial hyperplasia, which will also cause prolongation of menstrual period. 3. Organic diseases: prolonged menstrual period may also be caused by endometrial hyperplasia, endometrial polyps or endometrial cancer, submucosal fibroids and so on. In addition, other factors may also lead to the eighth day of menstruation is not clean, such as taking certain drugs or blood clotting function abnormalities, etc. It is recommended that the situation, timely to the hospital for examination, to clarify the cause of the disease, and then comply with the doctor’s instructions to deal with the treatment.