If it is a woman’s menstrual period stomach pain persists for several days may be normal, but it may also be caused by irritable bowel syndrome, appendicitis and other abnormal causes. 1. Menstruation: If a woman experiences constant stomach pain for several days, it may be caused by the onset of menstruation, which is generally a normal phenomenon. 2. Irritable bowel syndrome: Irritable bowel syndrome is a common gastrointestinal disorder. The common symptom is persistent stomach pain, and may be accompanied by diarrhea or constipation, but there is no organic disease. 3. Appendicitis: If the patient has appendicitis, as the appendicitis infection worsens, there may be persistent stomach pain, usually in the lower right abdomen. Constant stomach pain may also be caused by peritonitis, pancreatitis, myocardial infarction and other diseases. After excluding physiological causes, you should go to the regular hospital in time to find out the cause of the disease, and take targeted treatment measures under the guidance of professional doctors.