Like abortion, uterine clearance is an operation for miscarriage or tissue residue in the uterine cavity, which is harmful to the body, mainly in the following aspects: 1. The operation may damage the uterus, such as uterine perforation, which may lead to damage to organs around the uterus, such as intestinal canal and omental damage, and serious complications requiring surgery; 2. It may lead to bleeding, such as weak uterine contraction or uterine perforation, damage to the myometrium, all of which may lead to heavy vaginal bleeding; 3. Clearing the uterus may damage the endometrium, leading to bacterial upstream infection, resulting in endometrial or even pelvic infection, which may eventually lead to pelvic inflammatory disease, peri-tubal inflammation, secondary infertility or ectopic pregnancy; 4. Clearing the uterus may damage the basal layer of the endometrium, and postoperative adhesions in the uterine cavity as well as the cervical canal, leading to reduced menstrual flow, amenorrhea, dysmenorrhea, and The consequences are serious, so strict contraception must be recommended.