Why should a full-term newborn sleep on the right side after being fed?

The newborn's stomach is in a horizontal position. After feeding, it is recommended that they sleep on their right side to maintain airway patency, prevent milk regurgitation, and promote digestion.

1. Maintain Airway Patency

After feeding, newborns usually quickly fall asleep. If lying flat on their back during sleep, the base of the tongue may fall backward, potentially obstructing the airway and causing snoring. However, sleeping on the right side prevents this tongue displacement and helps keep the airway open. Moreover, if milk reflux occurs while the infant is lying on the right side, the milk typically flows out along the side of the mouth, reducing the risk of choking.

2. Prevent Milk Regurgitation

The lower esophageal sphincter in newborns is generally underdeveloped, making them prone to spitting up after feeding. Lying flat after feeding increases the likelihood of regurgitation. Since the stomach is primarily located on the left side of the body, sleeping on the right side does not compress the stomach or heart. Additionally, when a newborn lies on the right side after feeding, the cardiac (gastric) inlet (cardia) is elevated, which helps prevent milk from flowing back.

3. Promote Digestion

When newborns lie on their right side after feeding, pressure on the heart is minimized, improving blood supply and oxygenation to the intestines. This enhances intestinal motility, promotes digestion, and improves absorption of nutrients.