Eating small amounts of watermelon during menstruation is better because watermelon contains a lot of vitamins that can replenish the vitamins lost with menstrual blood. If you eat too much of it, especially frozen watermelon, it may cause abdominal pain and other menstrual discomforts, or even an increase in the amount of menstrual flow and prolongation of the menstrual period. Watermelon is a cool food, and eating too much of it can cause the uterus to become irritated, resulting in uterine contractions that lead to abdominal pain. During menstruation, the blood in the gastrointestinal tract is relatively reduced, so you need to pay attention to a reasonable diet to avoid gastrointestinal discomfort and avoid eating too much stimulating food. Lack of attention to diet and sudden changes in eating habits during menstruation may interfere with the normal menstrual cycle, resulting in a change in the duration of menstruation and a significant change in the amount of menstruation.