There are many causes of abdominal pain during menstruation, the common ones are: i. Stenosis of the cervix; ii. Hypoplastic uterus or poorly developed uterus; iii. Abnormal position of the uterus, such as extreme retroflexion or anterior flexion; iv. Psychoneurological factors can lead to hypersensitivity to pain in women; v. Genetic factors, which means that dysmenorrhea in daughters is linked to dysmenorrhea in mothers; vi. cause abdominal pain during menstruation; vii. increased prostaglandin content in the endometrium as well as in menstrual blood; viii. excessive contraction of the uterus; ix. abnormal contraction of the uterus; x. gynecological diseases, such as endometriosis, pelvic inflammatory disease, myometrium, uterine fibroids, intrauterine device placement; xi. excessive psychological stress in the first period of young girls, poor circulation of qi and blood due to sedentary lifestyle, poor menstrual blood flow, love of cold drinks etc.; twelve, the period of strenuous exercise, by the wind, cold, wet and cold invasion and so on. The last rare cause is the stimulation of certain industrial or chemical odors in the air, such as gasoline or banana water, etc., which may cause menstrual cramps.