Inguinal hernia. Illustration showing intestine (top) herniating into the scrotal sac. A hernia is the protrusion of an organ or tissue out through the wall of the body cavity in which it lies. An inguinal hernia occurs in the groin (inguen) when a sac of peritoneum, containing fat or part of the bowel, bulges through one of the inguinal canals. These are openings connecting the abdominal cavity and the scrotum in a male foetus. They provide a route for the descent of the testes into the scrotum, after which they disappear, but remain a weak spot in the abdominal wall. An inguinal hernia may result from physical straining or even from coughing. Surgical repair is usually required