The sac, which is formed from an outpouching of the peritoneum, protrudes in the midline, through the umbilicus (navel). It is normal for the intestines to protrude from the abdomen, into the umbilical cord, until about the tenth week of pregnancy, after which they return to inside the fetal abdomen. The<unk>  can be mild, with only a small loop of intestines present outside the abdomen, or severe, containing most of the abdominal organs. In severe cases surgical treatment is made more difficult because the infant's abdomen is abnormally small, having had no need to expand to accommodate the developing organs. Larger<unk> s are associated with a higher risk of cardiac defects.
Omphalocele
Gastroschisis
Encephalocele
Sialocele
Cranioschisis
Diaschisis
Spina bifida
Rachischisis