In order for a ventral hernia to form, there must be a hole, tear or weakened area in the abdominal wall near the umbilicus. This abnormal weakness allows the intestine to protrude through the hole or tear. The intestine forms a bulge underneath the skin.

Causes for weakness in the wall of the abdomen include:

• Birth defect:
• Abdominal wall develops abnormally in the womb.
• Abdominal injury
• Abdominal surgery