The size of the exomphalos depends on the number of organs exposed. This is usually the bowel but may include the liver and other organs. The sac containing the exposed organs is usually covered in a protective membrane. Sometimes exomphalos occurs in conjunction with other problems such as chromosomal (gene) or heart defects.
In gastroschisis some of the bowel has escaped through a hole in the abdominal wall and develops outside of the baby's abdomen. The bowel floats around in the amniotic fluid - this is a liquid that surrounds the unborn baby (fetus) - in the mother's womb for most of the pregnancy and sometimes the fluid irritates the bowel and makes it inflamed and thick, so that it does not work properly. Sometimes the bowel becomes twisted as it floats in the fluid and the blood supply is restricted. When the baby is born, the bowel is exposed to the air which sometimes causes further inflammation to occur.