Anatomy and embryology of abdominal wall defects.

Abdominal wall defects are one of the most frequently encountered human congenital anomalies. They are seen in as many as 1 in 2,000 live births with evidence to suggest that their incidence is increasing. While often discussed together abdominal wall defects consist mainly of two entities namely gastroschisis and omphalocele. There are marked differences in their theories of embryo-pathogenesis, clinical presentation/anatomy and overall outcomes. There is no clear consensus explaining the precise embryological mechanisms leading to the development of abdominal wall defects. Many clinicians and embryologists have attempted to explain the genesis of congenital abdominal wall defects because of failure of progression of various phases of normal embryonic development. This review summarizes the mechanisms involved in normal and abnormal development of the ventral abdominal wall leading to the development of gastroschisis and omphalocele.