Epidemiologic characteristics of congenital inguinal hernia.

957 of all the liveborn children in Budapest from 1962 to 1966 were operated for isolated congenital inguinal hernia until the age of 3 years, giving a point prevalence of 11.04 per 1000 livebirths. The sex ratio was 0.8892. 57% hernias occurred on the right, 26% on the left, and 17% on both sides. The occurrence of congenital inguinal hernia was significantly higher in infants born in colder winter months and in twinbirths. Babies with hernias had lower birthweights and shorter gestational ages. The role of potential teratogens could not be proved.