Vomiting usually refers to the reflex action of the stomach contents or even part of the intestinal contents going up in the digestive tract and expelling from the mouth for some reason, which is a manifestation of digestive tract dysfunction. Newborns are more prone to vomiting symptoms due to the dramatic changes in the environment inside and outside the womb, incomplete maturation of organs, poor resistance to the outside world, and the possible existence of various malformations. Etiology] Neonates are more prone to vomiting than children, mainly related to the characteristics of neonates, the common causes are as follows: 1, neonates have a more relaxed esophagus, small gastric volume, horizontal position, better development of the pyloric sphincter and poor development of the cardia sphincter, poor neural regulation of intestinal motility, higher abdominal pressure, all of which are anatomical and physiological causes of vomiting in neonates. 2, abnormalities in the differentiation and development of the organs during the embryonic period, especially in the anterior, middle and hind intestine, can easily cause malformations of the digestive tract, so that ingested food or digestive secretions cannot pass smoothly through the intestine and are discharged retrogradely from the mouth, resulting in vomiting. 3, the stimulation of the fetus at birth, such as swallowing a large amount of amniotic fluid, blood, as well as the rapid changes in the internal and external environment after birth, is also likely to induce vomiting in newborns. 4, the neonatal vomiting center is not well developed and is easily stimulated by systemic inflammation or toxins from metabolic disorders causing vomiting. Clinical manifestations] 1, asphyxia and sudden death neonatal vomiting will make vomit into the respiratory tract, asphyxia, such as vomit, not timely detection can lead to sudden death. 2, inhalation syndrome vomit into the airway can occur aspiration pneumonia, coughing, breathing difficulties, prolonged repeated inhalation can make aspiration pneumonia persistent. 3, apnea premature infants vomiting can occur apnea. 4, bleeding Violent vomiting can lead to gastric mucosa damage, bleeding, vomit is bloody. 5, water-electrolyte disorders more frequent vomiting, due to the loss of large amounts of water and electrolytes, resulting in water-electrolyte balance disorders, the child dehydration, acidosis, hyponatremia, etc.. Diagnosis] The diagnosis of neonatal vomiting is mainly etiologic and determines whether there is an abnormality of the digestive tract that requires urgent surgical treatment. The diagnosis is made based on the frequency, nature, amount of vomiting, onset time, development trend, accompanying symptoms and the presence of complications, combined with X-rays, gastrointestinal imaging and other ancillary tests. 1. Symptoms: vomiting episodes are less frequent, the vomiting volume is small and dominated by gastric contents, does not contain bile or fecal-like material, no obvious malnutrition and developmental disorders, not accompanied by abdominal distension as well as constipation, etc. Most of the vomiting episodes that gradually improve with time and medical treatment are due to medical causes, common physiological gastroesophageal reflux, improper feeding, gastric mucosa irritation, gastrointestinal dysfunction, infectious diseases inside and outside the intestinal tract, the central nervous system diseases, etc. Frequent seizures, large amount of vomit affects nutritional status and growth, bilious, coffee-like or fecal-like vomiting, accompanied by abdominal distension, constipation and abdominal pain, and those who do not improve even after medical and postural treatment and correct feeding are mostly due to gastrointestinal malformations, common causes are congenital esophageal atresia, diaphragmatic hernia, pyloric hypertrophic stenosis, pyloric valve or atresia, annular pancreas, intestinal malrotation, intestinal atresia or stenosis, congenital giant colon, anorectal malformation, etc. Rarely, there are also neonatal necrotizing small intestine colitis, fetal fecal peritonitis, gastric rupture of gastric muscle layer dysplasia, etc. 2, auxiliary examinations: X-ray and gastrointestinal tract imaging are the main ones. x-ray film suggests intestinal obstruction or abnormal gastrointestinal tract structure and the location of the obstruction is confirmed by gastrointestinal tract imaging can make the corresponding diagnosis. Treatment] The diagnosis and treatment of neonatal vomiting are intertwined, and the principles of treatment include prevention of complications and etiology. These include prevention of aspiration, improvement of feeding habits, control of infection, and surgical correction of digestive tract deformities.