49 years old half a year without menstruation suddenly came again may be endometrial polyps, uterine fibroids, cervical cancer and other diseases. 1. Endometrial polyp: its etiology is not yet clear, may be due to high estrogen level, long-term gynecological inflammation stimulation, intrauterine foreign body stimulation, puerperal infection, obesity and other factors. Patients may have abnormal menstruation, postmenopausal vaginal bleeding, manifested as 49 years old half a year without menstruation suddenly came back. 2. Uterine fibroids: the causes of uterine fibroids include heredity, childlessness or late childbearing, abnormal sex hormone level and so on. Patients may have abnormal menstruation, non-menstrual vaginal bleeding and other symptoms, and some patients may have the situation that they have not had menstruation for half a year at the age of 49 and suddenly come back. 3. Cervical cancer: cervical cancer is also considered as the cause of cervical cancer when a patient is 49 years old and hasn’t had menstruation for half a year and suddenly has menstruation again. Its cause is related to human papilloma virus infection, low immunity, multiple pregnancies and births, smoking and other factors. Patients may experience symptoms such as contact bleeding, abnormal vaginal bleeding, and postmenopausal bleeding. There are many reasons why a 49-year-old woman who has not had her period for half a year suddenly has it again, and it is recommended that the patient consult a doctor in time to find out the cause of the disease.