A hernia is a protrusion of a piece of the intestine through an abnormal opening.
Some infants are born with a diaphragmatic hernia (see Birth Defects: Diaphragmatic Hernia). A diaphragmatic hernia is a hole or weakening in the diaphragm (the muscle that separates the chest from the abdomen and that helps in breathing). This opening allows some of the small intestine to push through the opening, creating a bulge. Sometimes the intestine becomes trapped (incarcerated) in the opening. Sometimes incarceration cuts off the blood supply to the trapped intestine (strangulation), which can lead to a tear (perforation) and peritonitis (inflammation and usually infection of the abdominal cavity and its lining), creating a surgical emergency. A large diaphragmatic hernia can decrease lung volume and create breathing problems. Doctors do a surgical procedure to correct this type of hernia. A diaphragmatic hernia that bulges through the opening that the esophagus normally passes through (the hiatus) is called a hiatus hernia (see Hiatus Hernia, Bezoars, and Foreign Bodies: Hiatus Hernia).
An umbilical hernia is a small opening in the abdominal wall near or at the belly button (umbilicus). The small intestine can protrude through the opening when the child coughs or strains during a bowel movement. The intestine rarely becomes trapped (incarcerated), and the hernia usually closes without treatment by the time the child is 5 years of age. If a large umbilical hernia does not close by that time, the doctor may advise surgery. Folk remedies such as taping a coin or other object over the hernia do not work and may irritate the skin.
A hernia in the groin is called an inguinal hernia (see Gastrointestinal Emergencies: Inguinal Hernia). Inguinal hernias are more common among boys, particularly those who are premature. About 10% have hernias on both sides of the groin. Because inguinal hernias can become incarcerated, doctors usually advise surgery.
Last full review/revision November 2012 by William J. Cochran, MD