A groin or inguinal hernia can occur on one or both sides of the groin or scrotum. An inguinal hernia may be unilateral, occurring on one side of the groin, or bilateral, occurring on both sides of the groin. The majority of hernias are in this area and are most common in men. About 70% of inguinal hernias are indirect. This type of hernia occurs in a natural weak spot of the groin around the spermatic cord. About 30% of inguinal hernias are direct. This type of hernia occurs from weak tissue being aggravated by straining or lifting over time.
Any one of these hernias may be recurrent. This means that a previously repaired hernia has returned. People with especially weak abdominal walls or multiple surgical sites may simultaneously suffer from a combination of types of hernias.