What is a hernia? Muscle is usually covered in a tissue that gives it strength called fascia. A hernia is a
hole in this fascia or muscle, and can be present at birth (congenital) or can develop
over time (acquired). There are many kinds of hernias with most of them being
located in various parts of the abdomen. Increased pressure on one side of the
hernia can push tissue, fat, or body organs into and through the hole, which can
cause pain and a bulge under the skin.