Sometimes no apparent cause is found for developed inguinal hernia.
However, the main predisposing factors are abdominal wall weakness, conditions that lead to increased abdominal pressure, or combination of two.
Babies and young people, often, have indirect inguinal hernia, that is usually unilateral (only one side).
Less then 10% of inguinal hernia are bilateral and often, an undergoing collagen metabolism disorder plays a role in abdominal weakness.
Middle aged and older men have direct hernia that is bilateral in more cases.
Up to 10% of hernias may develop again, often during period of 2 years following the successful surgery.