Hepatitis A and Down's syndrome: lack of an association.

The occurrence of hepatitis A early in pregnancy has been reported to result in increased births of children with Down's syndrome. Eleven sets of paired sera were obtained before conception and during pregnancy from women who delivered infants with Down's syndrome. These sera were tested for antibody to hepatitis A virus with use of immune electron microscopy. None of the women had seroconversions or increases in levels of antibody to hepatitis A virus. No evidence of an association between hepatitis A and Down's syndrome was found in the women studied.