Red degeneration of uterine fibroids is caused by ischemia, necrosis, hemolysis, thrombosis, embolism and infiltration of hemolyzed blood into the tumor. Its incidence is 1.9% to 25%, of which pregnancy-related accounted for 20.3% to 34.8%. And mostly in the middle of pregnancy, with subplasma leiomyoma is common, the patient may appear severe abdominal pain with fever, usually around 38 ℃, white blood cell increase, check the tumor localized obvious pressure pain, the vast majority of about a week can be recovered.