Stomach pain during menstruation may be related to gastrointestinal diseases, adverse factors before menstruation and hormonal changes during menstruation. 1. Gastrointestinal diseases: If you have gastrointestinal diseases, when you have your period, your body’s resistance will be weaker, and if you get cold or eat improperly, you may have stomach discomfort. 2. Adverse factors before menstruation: If there are many bad habits before menstruation, such as getting cold, excessive fatigue, improper emotion, improper diet, you may also have stomach upset, such as stomach pain and other symptoms. 3. Hormonal changes during menstruation: During menstruation, the hormone levels in a woman’s body will change and she may experience discomfort in her body, such as stomach pain and bloating. Therefore, during menstruation, women should pay attention to keep warm, eat less cold or spicy food, and also avoid strenuous exercise or heavy physical labor.