The presence of endocrine hormonal disorders such as prolactinemia, polycystic ovary syndrome, low estrogen, and low progesterone may cause endometrial abnormalities that may lead to bleeding. Uterine lesions such as human papillomavirus infection, fibroids, cervical canal polyps, endometrial polyps, endometrial inflammation, including adnexal cysts, may also cause bleeding; cervical columnar epithelial ectropion, or cervical erosion, may cause bleeding due to irritation during intercourse. In such cases, you should go to the hospital for endocrine hormone examination, ultrasound, colposcopy, etc. to confirm which cause of bleeding is involved, so that you can treat the symptoms and stop the bleeding.