Milk overflow: The reason for milk overflow is because of the baby’s development, especially the digestive tract, the baby’s stomach is in a horizontal position, the entrance is called the cardia, which is particularly flaccid, and the exit is called the pylorus, which is particularly tightly developed. This is why babies tend to overflow after eating milk. What should I do when I have a milk spill? Pick up your baby after breastfeeding, hold him or her upright and then pat his or her back and burp. Change the diaper before breastfeeding and keep a comfortable position to avoid overchanging the baby’s position after breastfeeding to cause overflow.