This is due to the change in endocrine hormone levels during menstruation, the body produces too much prostaglandin and sex hormone levels change, personal constitution and other effects, it will cause stimulation of the intestinal tract, so the symptoms appear. This is not a disease of the intestines, and will not be harmful, you can carry out diet, regular diet, pay attention to rest, avoid cold, avoid strain, after the menstrual period hormone level is normal symptoms will naturally recover, will not cause harm to health.