The defecation habits of newborns are related to the way they are fed, but it is considered abnormal for both breastfed and formula-fed newborns not to have a bowel movement for 4 days, and most of them are constipated, but care should be taken to identify congenital megacolon. The defecation habits of newborns (such as the number of bowel movements per day and the shape of the stools) are related to their feeding methods, and there are also individual differences. For formula-fed newborns, the stools are usually passed about 1~2 times per day or every other day, and for exclusively breastfed newborns, the number of stools is slightly higher, with 2~4 bowel movements per day, and some of them may be passed 4~5 times, and they are usually in a good general condition, with a satisfactory weight gain. For newborns 4 days without stool, for no matter which way of feeding the baby is considered abnormal, most of them are seen in constipation, can be used as appropriate to soften the stool, easy stool discharge. However, attention should be paid to identify congenital megacolon, such babies have delayed expulsion of meconium, clinical symptoms such as vomiting, abdominal distension, and some have intestinal obstruction. In addition, we should also be alert to the possibility of congenital anus. It is recommended to consult a specialist for evaluation and management.