Aunt refers to menstruation. The causes of bleeding below the period are dysfunctional uterine bleeding, organic diseases of the uterus and cervix, and gestational trophoblastic diseases. 1. Dysfunctional uterine bleeding: abnormal uterine bleeding caused by dysfunction of the hypothalamic-pituitary-ovarian gonadal axis that regulates reproduction without organic lesions of the whole body and reproductive organs. 2. Organic diseases of uterus and cervix: endometrial polyp, submucous fibroid, cervical polyp, endometrial cancer, cervical cancer, etc., all of which may cause non-menstrual bleeding. 3. Gestational trophoblastic diseases: Gestational trophoblastic diseases, including hyperemesis gravidarum, erosive hyperemesis gravidarum, choriocarcinoma, placental trophoblastic tumors and epithelioid trophoblastic tumors, may have non-menstrual bleeding. When abnormal vaginal bleeding occurs, one should seek medical treatment promptly.