Abstract
The incidence of major malformations following maternal chickenpox, mumps, measles, and viral hepatitis was observed in a controlled, cohort study of offspring followed up until five years of age. Major congenital defects occurred in each viral group, but the malformations were equal in frequency and often similar in type to those observed among comparable controls for the respective viral groups. Consequently, the malformations that occurred could not be attributed directly to the associated diseases under study.