Women with dysmenorrhea are clinically divided into primary dysmenorrhea and secondary dysmenorrhea. Primary dysmenorrhea: It is caused by the release of more prostaglandins from the endometrium when menstruation occurs. Secondary dysmenorrhea is often caused by the following clinical reasons: 1. endometriosis, which can cause persistently aggravated dysmenorrhea, and this dysmenorrhea is often found in the pelvic cavity or myometrium through ultrasound examination. 2. inflammation of the pelvic cavity, due to inflammation of the pelvic cavity clinically, there will also be pain in the lower abdomen when menstruating. 3. Tumors of the pelvis, such as uterine fibroids or tumors of the pelvis, can also cause menstrual pain clinically. 4. Due to abnormal uterine development, such as longitudinal uterus and unicornuate uterus can lead to menstrual pain.