Level 1: Reasons for newborn infants to spit up: 1. Improper feeding leads to vomiting 2. Gastrointestinal problems cause vomiting 3. Overfeeding or eating too fast causes vomiting The gastrointestinal function of newborn babies is not fully developed, and the digestive ability is weak , prone to vomiting. Improper feeding is one of the main causes of spitting up in newborn babies. If the mother\’s posture when breastfeeding is incorrect or the feeding time is too long, it will cause the baby to