One hundred eighty-nine women who were immunized with Influenza A/New Jersey/8/76 virus vaccine (InfA/NJ) just prior to or during their pregnancy were compared with a control group of 517 pregnant women who did not receive the vaccine. This longitudinal, prospective study demonstrated no association between immunization with InfA/NJ and maternal, perinatal, or infant complications. No teratogenicity was demonstrated, and the two groups of infants did not differ in physical or neurological assessments at birth and at 8 weeks of life.