What should I do if my baby spits up milk? Cause analysis: Babies spitting up milk is a common phenomenon, and the reasons may come from many aspects. The most common cause is indigestion due to the baby consuming too much milk. At the same time, babies’ digestive systems are relatively fragile and are easily affected by infections, leading to indigestion. In addition, if the baby\’s posture is incorrect when feeding, inhaling too much air can also cause spitting up. Prevention methods 1. Control the amount of milk each time to avoid excessive fullness. 2. Pay attention to the baby\’s posture when feeding. It is recommended to feed the baby in a semi-lying or prone position, which is beneficial to digestion.