Low back pain during menstruation may be caused by increased prostaglandins, bad lifestyle habits, reproductive system diseases and other reasons. 1. Increased prostaglandins: When a woman is menstruating, the prostaglandins synthesized by the endometrium are too high, which may lead to excessive contraction of the uterine smooth muscle, and spasmodic contraction may cause dysmenorrhea, resulting in low back pain. 2. Bad habits: some women often use cold water to take a bath, or often eat some cold food, resulting in abdominal cold, causing menstrual blood discharge is not smooth, dysmenorrhea may occur, radiating to the lumbosacral region, resulting in lumbar pain symptoms. 3. Reproductive system diseases: when suffering from chronic adnexitis, pelvic inflammatory disease, salpingitis, uterine fibroids and other reproductive system diseases, may also trigger pelvic congestion, resulting in low back pain symptoms. Causes of low back pain during menstruation are many, if the symptoms of low back pain are more serious, it is recommended to go to the hospital in a timely manner, to clarify the cause of the cause under the guidance of the doctor for the cause of the treatment.