Great aunt refers to menstruation. Menstrual pain and lumbago may be a normal physiological phenomenon, or it may be caused by chronic pelvic inflammatory disease, endometriosis and other diseases. 1. Physiological phenomenon: the phenomenon of menstrual pain and lumbago is mostly due to the rise in estrogen levels and increased secretion of prostaglandins during menstruation, causing pelvic congestion, resulting in vasodilatation and smooth muscle contraction. Some people will also be accompanied by lower abdominal discomfort, anal discomfort, breast pain and other symptoms, which is a normal physiological phenomenon, do not worry too much. 2. Chronic pelvic inflammatory disease: the disease is mainly due to the internal genital organs and the surrounding connective tissue, pelvic peritoneum due to the existence of chronic infection. The disease can cause pelvic inflammation, resulting in adhesions, scarring and pelvic congestion, leading to the phenomenon of menstrual back pain and lumbago. Patients may also suffer from lower abdominal distension and pain, menstrual abnormalities and other symptoms. 3. Endometriosis: the disease is related to the reverse flow of menstrual blood, heredity, endocrine function abnormality and other factors, when the ectopic endometrial tissue invades the pelvic organs and wall peritoneum, etc., it can cause the phenomenon of menstrual back pain and lumbago. In addition, the patient is accompanied by symptoms such as abnormal menstruation, painful intercourse and acute abdominal pain. In addition, cold abdomen, overwork and so on can also cause menstrual back pain and lumbago, it is recommended to go to the hospital in time for examination, to clarify the cause of the disease, in order to follow the doctor’s instructions for the appropriate treatment.