Menstruation may be delayed after bone fracture surgery. Possible causes include malnutrition, endocrine disorders and pregnancy. 1. Malnutrition: After fracture surgery, the body is in a weak state, if there is no timely supplementation, resulting in malnutrition, menstruation will be delayed, and after reasonable supplementation, menstruation can return to normal. 2. Endocrine disorders: due to the trauma of fracture surgery, emotional changes such as anxiety, tension, plus the influence of the environment, it is easy to have endocrine disorders, delayed menstruation, after regulating emotions, adequate rest, and changing the environment, the menstrual cycle will return to normal. 3. Pregnancy: After fracture surgery, if the delayed menstruation is too long and accompanied by symptoms of pregnancy, human chorionic gonadotropin assay is needed to exclude the delayed menstruation caused by pregnancy. If menstruation is delayed for a long time after fracture surgery, it is recommended to go to the hospital for early treatment.