Newborns with milk flaps can be caused by undigested milk, lactose intolerance and impaired gastrointestinal function. 1. Undigested: Milk flaps are usually produced when the protein or fat in food is not fully digested. The underlying cause is related to the baby’s small size and lack of digestion and absorption ability. 2. Lactose intolerance: Lactose intolerance can lead to diarrhea, which in turn causes the baby’s intestinal digestion and absorption of proteins and fats is poor, appearing newborns pulling milk petals. 3. Gastrointestinal function is impaired: the baby in the cold or gastrointestinal tract infection will affect the gastrointestinal tract of the digestive function, so that the baby pull milk petals. Parents need to pay attention to the baby to keep warm when cold, gastrointestinal tract infection, please consult a doctor in time. If your newborn’s wheezing doesn’t subside for a long time, please consult a doctor immediately to find out the cause of the problem.