More than 40 days of the baby tongue, may be physiological factors, there may be pediatric gastroenteritis, cerebral palsy and other disease causes. 1. Physiological factors: more than 40 days baby tongue may be outside the adult teaching, or out of curiosity to imitate the psychological, constantly tongue to express the inner needs. In addition, this stage of the baby’s salivary gland development, will secrete a lot of saliva, will also appear constantly spit out the phenomenon of the tongue. 2. Pediatric gastroenteritis: Pediatric gastroenteritis is generally due to a variety of factors such as exposure to cold, decreased immunity, the body appears to be bacterial, or viral infections. Some babies will have different degrees of diarrhea, loss of appetite, abdominal pain and other symptoms, and may also vomit and spit out the tongue. 3. Cerebral palsy: A very small number of babies are born with hypoxia, resulting in non-progressive brain damage. Such children mainly show central motor disorder and sensory perception disorder, etc. In the early stage, children will have upper limb flexion, feeding difficulty, swallowing difficulty and frequent spitting and tongue spitting behaviors. There may be other reasons for a 40-day-old baby to spit out his tongue, so it is recommended to go to the hospital in time for a complete examination to determine the cause of the disease, and then give targeted treatment under the guidance of the doctor.