Abdominal wall defects of the newborn

Congenital abdominal wall defects are a heterogeneous group. The two main types are omphalocele and gastroschisis, both originating early in development. Omphalocele is characterized by a herniation of abdominal contents through the umbilical insertion and covered by a membrane which may or may not be intact. (It can be confused with umbilical hernia, which is caused by a weakness or tearing of the navel during birth.) In a large percentage of infants with omphalocele, other malformation are present, often severe ones (omphalocele may be part of a genetic or chromosomal syndrome). This causes high mortality. Gastroschisis (or para-umbilical hernia) is characterized by herniation of the intestines through an abdominal wall defect to the side of the intact umbilical cord, as is usually unaccompanied by other malformations. More minor omphaloceles and most gastroshises can be repaired surgically to complete normality.

The rate of abdominal wall defects are around 2 to 4 births per 10,000. Gastroschisis is associated with low maternal age and ompahlocele with a high maternal age. A decreasing rate in certain countries in recent years is possibly the result of prenatal diagnosis and selective abortion. An increasing rate has been reported in Sweden.