The appearance of menstruation to be unable to get down to the stomach pain can be seen in physiological dysmenorrhea response, organic lesions, inflammatory lesions, pelvic inflammatory disease, pregnancy-related lesions, and so on. 1. Dysmenorrhea: The synthesis and release of prostaglandins in the body increases, prompting uterine contractions leading to pain, and the uterine cavity is filled with menstrual blood, exacerbating the symptoms of abdominal pain. Generally, the discomfort will disappear after the onset of menstruation. 2. Organic lesions: endometriosis and adenomyosis are common, and some of them can be manifested as lower abdominal pain starting before menstruation. In addition, the uterine cavity adhesion, cervical tube adhesion, etc. can also cause the menstrual blood flow is not smooth, manifested as menstruation does not come but have obvious abdominal pain. 3. Inflammatory lesions: because the inflammatory factors produced by bacteria or viruses stimulate the contraction of the endometrium and cause premenstrual pain in the lower abdomen, but this pain will persist in the menstrual period and may be aggravated. 4. Pregnancy-related lesions: often manifested by a history of menopause, lower abdominal pain, and in some cases, abnormal vaginal bleeding. For example, ectopic pregnancy, inevitable abortion. If the symptoms of severe pain in the stomach when menstruation is about to come, please consult a doctor in time to find out the causative factors with the help of the doctor, and do not take medication without authorization, in order to avoid adverse consequences.