Diarrhea during menstruation may be caused by physiological reasons, or may be caused by acute enteritis, gastrointestinal dysfunction and other reasons, which need to be analyzed specifically. 1. Physiological reasons: when a woman is menstruating, the endometrial stripping stimulates the contraction of the uterus, and at this time, it is possible to stimulate the back of the intestinal tract, causing diarrhea symptoms. 2. Acute enteritis: acute inflammation caused by pathogenic bacteria invading the mucosa of the gastrointestinal tract, often caused by eating unclean food or irritating food, coupled with the lower resistance during menstruation, can be manifested as diarrhea and abdominal pain and other symptoms. 3. Gastrointestinal dysfunction: the mood during menstruation may be very poor, produce some anxiety, depression and other situations, at this time may cause gastrointestinal dysfunction, manifested as diarrhea and other symptoms. Diarrhea during menstruation may also be other reasons, should be timely to the hospital, improve the relevant examination to clarify the cause of the disease, under the guidance of the doctor symptomatic treatment.