The incidence of contralateral patent processus vaginalis in unilateral inguinal hernia in Nigerian children.

A prospective study was carried out to determine the incidence of contralateral patent processus vaginalis in unilateral inguinal hernia in Nigerian children. Over a 5-year period (1977-1981), all children under 8 years of age with unilateral inguinal hernia underwent planned bilateral groin exploration. The highest frequency was recorded in the under 1 year age group (39%); there was a steady decline with age: at 2 years 22% and beyond 2 years of age it levelled out to 17%. Beyond the age of 5 years, contralateral groin exploration was negative. The frequency in Nigerian children is lower than in their Caucasian counterparts; this may be due to genetic and/or environmental factors.