Long, dripping periods, if the bleeding comes from the uterine cavity, fall under the category of abnormal uterine bleeding and are related to age and history of sexual intercourse. Possible causes are:1. If there is a history of sexual intercourse, pregnancy must be excluded. Need to check blood HCG and ultrasound. 2, irregular menstruation, endocrine disorders, need to do hormone level measurement, to understand the ovulation and ovarian function. 3, local factors in the uterine cavity, such as endometrial polyps, submucosal leiomyoma, endothelial lesions, etc., need to do gynecological ultrasound, hysteroscopy if necessary. 4, other factors, such as taking contraceptives or other medications that may cause bleeding, nervousness, fatigue, stress, etc., labor, stress and so on. In addition to bleeding from the uterine cavity, bleeding time, but also need to rule out the cervical factors caused by bleeding, have a history of sexual intercourse, need to check the cervix, cervical cytology and HPV test, to understand the cervical abnormalities.