Sudden constipation in babies may be due to the following reasons: 1, dietary reasons, the diet structure and eating habits are unreasonable, may be to feed the baby too much, eat food that is not easy to digest; 2, the baby’s own reasons, may be the baby originally poor gastrointestinal function, intestinal flora imbalance, gastrointestinal malfunction, etc.. So what should babies do if they are constipated? First of all, we should regulate the diet, do not feed the baby too much at a time, to eat less and more meals, feed more times, followed by appropriate with some easily digestible food, food containing more fiber, usually pay attention to give the baby more water, which also helps defecation. Secondly, babies with bad stomach can take some probiotics to regulate the flora in the intestinal tract, which will help the baby’s bowel movement.