Three-month-old babies who have not pooped for three days may be a normal phenomenon, or it may be caused by pathological factors such as indigestion, which can be treated with appropriate nutritional supplements or medication. 1. Normal phenomenon: because the baby’s digestive system is still developing, if the body produces too little food residue every day, can not promote rectal defecation, it will cause three-month-old babies three days without poop phenomenon, can be properly supplemented to ensure that the baby’s health, when the body of the amount of food residue reaches a certain level, the baby will return to normal defecation. 2. Pathological factors: If the three-month-old baby eats too much, there will be intestinal flatulence, bowel movements to reduce the number of dyspepsia and other manifestations, which can be manifested as three days without stool, parents can give the baby to take, such as compound pepsin powder to help digestion, Bacillus cereus bacilli bacillus to regulate the intestinal flora, and with the massage of the baby’s abdomen and so on, to promote the smooth discharge of stools. Three-month-old babies three days without poop can also be caused by constipation, congenital megacolon and other diseases, it is recommended to go to the hospital in a timely manner, after the cause of the disease is clear according to the doctor’s guidance for standardized treatment. The above medications should be used in accordance with medical advice.