Groin hernia is a weakness in the muscles and tissues of the groin.

Both men and women have natural weaknesses in the tissues of the inguinal canal, a passage from the inside of the abdomen to the scrotum in men and labia in women. This passage normally seals off during development. An indirect inguinal hernia occurs when the inguinal canal does not close completely. Over time, this opening enlarges and organs in the abdomen push into the canal. A direct inguinal hernia occurs when the weakness is in the floor of the inguinal canal rather than through its opening. Direct and indirect hernias cause similar symptoms and look nearly the same on physical examination. Lower in the groin, another area that can form a hernia is the femoral canal, which contains blood vessels that travel from the abdomen to the legs.

Factors associated with development of groin hernias include smoking, long-term coughing, obesity, and straining during urination or bowel movements. Groin hernias are more common in men—25% develop a hernia over the course of their lifetime. Indirect hernias are the most common groin hernia in men and women. Femoral hernias most often occur in women and most frequently require surgery.