Low back pain during menstruation may be due to dysmenorrhea, or it may be caused by endometriosis or adenomyosis. 1. Dysmenorrhea: During menstruation, there is pelvic congestion and prostaglandin levels increase dramatically, which can lead to dysmenorrhea, which can be manifested as pain in the lower back. 2. Endometriosis: If the back pain during menstruation is obvious and progressively aggravated, it may be caused by endometriosis, which is an abnormal endometrium with poor discharge of menstrual blood and will stimulate the pelvis to produce pain. 3. Uterine adenomyosis: if women’s menstrual back pain gradually worsened, and can feel a hard mass in the abdomen, need to consider the possibility of uterine adenomyosis, the uterus increases in size, the pelvis is also stimulated by inflammation, resulting in menstrual back pain. There are other possible causes of menstrual back pain. If a woman experiences mild back pain during menstruation, she can be observed regularly. However, if secondary dysmenorrhea occurs and worsens progressively, endometriosis, adenomyosis or other diseases need to be considered, and the patient can go to the hospital in time to clarify the cause for further treatment.