Background: The fetal varicella syndrome is associated with abnormal central nervous system development, which in many cases is associated with mental retardation. However, the incidence of neurobehavioral deficits in asymptomatic structurally normal children whose mothers had clinically diagnosed varicella-zoster virus infection is unknown.
Methods: Neurobehavioral outcome was evaluated in 84 children born to women infected with varicella during pregnancy and 40 children born to women who were not infected with varicella during pregnancy. Children were 3 to 15 years of age at the time of testing. Clinical features of the fetal varicella syndrome were present in only 1 of the 84 children in the varicella group. These sample sizes provide statistical power of 0.80 (alpha = 0.05) to detect group differences of 0.54 sd (the equivalent of 8.1 IQ points).
Results: No differences were found in the test performance of the two groups. In addition, within the varicella sample, no meaningful differences were found relative to infection-related hyperthermia or the timing of infection.
Conclusions: As a group, the children born to women infected with varicella-zoster virus during pregnancy and who do not have structural features characteristic of the fetal varicella syndrome are not neurodevelopmentally different from unexposed, uninfected control children.