At three months old, a baby’s stomach capacity is small and the lower esophageal sphincter is not fully developed. If the baby lies down immediately after feeding, milk may leak out of the mouth, even causing them to regurgitate all the milk they have just eaten. This type of regurgitation is medically referred to as overflow milk. Generally, no medication is needed. It is important to immediately expel the milk from the mouth and nose to prevent aspiration. As the baby grows older, the symptoms of bloating will gradually diminish, and by around six months of age, the symptoms will basically cease.