A case of disseminated herpes simplex virus infection during pregnancy is reported, and 26 similar cases are reviewed. The present case was unusual in that it occurred in the 12th week of gestation, where as all but one of the other cases occurred in the secondor third trimester. This rare complication is generally preceded by a flu-like prodrome with or without oral or genital lesions. The clinical presentation is (1) encephalitis without hepatic involvement, (2) hepatitis with or without central nervous system findings, or (3) disseminated skin lesions. When the liver is involved, rapidly progressive hepatic necrosis and severe coagulopathy are common and the mortality is high. Early diagnosis and early institution of antiviral chemotherapy with acyclovir greatly improve the out come for both mother and infant.