Having a period for 20 days is abnormal uterine bleeding. There are more reasons for bleeding, which may be caused by endocrine disorders, or ovarian tumors, submucosal fibroids or intermucosal fibroids affecting the endometrium, or adenomyosis, endometriosis, or endometrial polyps or precancerous endometrium, all of which can cause irregular vaginal bleeding or menstrual Therefore, it is important to go to the hospital for ultrasound examination as soon as possible. If it is caused by a tumor, surgery is needed. If it is caused by endometrial thickening, you need to do scraping and then do pathological examination to determine the next step of treatment according to the pathological results. If it is caused by endocrine disorder, it needs to be treated by menstrual regulation and hemostasis.