Abnormal uterine bleeding or premenstrual abortion is caused by gynecological diseases. Abnormal uterine bleeding can be caused by endocrine disorders, or bleeding caused by taking emergency contraceptive pills, or gynecological diseases such as endometrial polyps, submucosal fibroids, or adenomyosis. If menstruation comes back after menopause, ultrasound examination should be carried out in time to find out the condition of the uterine adnexa and the endometrium, and gynecological examination should be carried out to find out the condition of the cervix, and to find out whether the source of bleeding is the cervix or the uterine cavity. Women of childbearing age who are not using contraception should also undergo a blood HCG test to find out whether the bleeding is caused by pre-eclampsia, and according to the results of the test, effective treatment should be given to the symptoms.