Uterine fibroids are the most common benign tumors of the female reproductive system, with the possibility of malignant transformation, but the chance of malignant transformation into smooth muscle sarcoma is rare, about 0.4-0.8%. It is often seen in postmenopausal patients whose fibroids do not shrink but increase in size, and may be accompanied by irregular vaginal bleeding. If the fibroids are found to be growing rapidly within a short period of time, with menstrual disorders and abdominal pain, and if the ultrasound indicates that the fibroids are rich in blood flow with unclear borders, surgery is required as soon as possible. The doctor will send a frozen section for pathological diagnosis to determine the nature of the fibroids, determine whether they are degenerative or malignant, and formulate a treatment plan in time. Therefore, patients with uterine fibroids need to have regular ultrasound examinations, and those who have an increase in size within a short period of time or whose ultrasound suggests an abundance of tumor blood flow or abnormal tumor markers, and those whose fibroids have not shrunk but have increased in size after menopause, need surgery. It is especially important to follow up postmenopausal women with fibroids, and it is generally recommended to check them once every six months to once a year, or longer if the fibroids are gradually shrinking.