A hernia may be congenital and present at birth or it may develop over time in areas of weakness within the abdominal wall. Increasing the pressure within the abdominal cavity can cause stress at the weak points and allow parts of the abdominal cavity to protrude or herniate.
Increased pressure within the abdomen may occur in a variety of situations including chronic cough, increased fluid within the abdominal cavity (ascites), peritoneal dialysis used to treat kidney failure, and tumors or masses in the abdomen. The pressure may increase due to lifting excess weight, straining to have a bowel movement or urinate, or from trauma to the abdomen. Pregnancy or excess abdominal weight and girth are also factors that can lead to a hernia.