Ten pregnant women with varicella and one pregnant woman with herpes zoster were studied. Only one of these women had a complicated course characterized by nephritis and hepatitis and the birth of a stillborn infant. One other woman who had vaginal bleeding for a month prior to the onset of varicella aborted two weeks after recovery from varicella. Seven women who were observed to term delivered normal, full-term infants. Large doses of γ-globulin which were given to four infants whose mothers had varicella within a week prior to delivery failed to produce a detectable rise in serum varicella-zoster (V-Z) antibodies. Three of these infants who were born without V-Z serum antibody got neonatal varicella. All recovered uneventfully.