Gastroschisis is a birth defect in which the babys intestines extend outside of the abdomen through a hole next to the belly button. The size of the hole is variable, and other organs including the stomach and liver may also occur outside the babys body. Complications may include feeding problems, prematurity, intestinal atresia, and intrauterine growth restriction.The cause is typically unknown. Rates are higher in babies born to mothers who smoke, drink alcohol, or are younger than 20 years old. Ultrasounds during pregnancy may make the diagnosis. Otherwise diagnosis occurs at birth. It differs from omphalocele in that there is no covering membrane over the intestines.Treatment involves surgery. This typically occurs shortly after birth. In those with large defects the exposed organs may be covered with a special material and slowly moved back into the abdomen. The condition affects about 4 per 10,000 newborns. Rates of the condition appear to be increasing. Signs and symptoms
There are no signs during pregnancy. About sixty percent of infants with gastroschisis are born prematurely. At birth, the baby will have a relatively small (<4 cm) hole in the abdominal wall, usually just to the right of the belly button. Some of the intestines are usually outside the body, passing through this opening. In rare circumstances, the liver and stomach may also come through the abdominal wall. After birth these organs are directly exposed to air. Causes
The cause of gastroschisis is not known.
The forces responsible for the movement of the lateral body wall folds are poorly understood, and a better understanding of these forces would help to explain why gastroschisis occurs mostly to the right of the umbilicus, while other ventral body wall defects occur in the midline.At least six hypotheses have been proposed for the pathophysiology:

Failure of mesoderm to form in the body wall
Rupture of the amnion around the umbilical ring with subsequent herniation of bowel
Abnormal involution of the right umbilical vein leading to weakening of the body wall and gut herniation
Disruption of the right vitelline (yolk sac) artery with subsequent body wall damage and gut herniation
Abnormal folding of the body wall results in a ventral body wall defect through which the gut herniates
Failure to incorporate the yolk sac and related vitelline structures into the umbilical stalkThe first hypothesis does not explain why the mesoderm defect would occur in such a specific small area. The second hypothesis does not explain the low percentage of associated abnormality compared with omphalocele. The third hypothesis was criticized due to no vascular supplement of anterior abdominal wall by umbilical vein. The fourth hypothesis was commonly accepted, but it was later shown that the right vitelline artery (right omphalomesenteric artery) did not supply the anterior abdominal wall in this area. More evidence is needed to support the fifth hypothesis.