ABSTRACT: Genital herpes simplex virus (HSV) infection during pregnancy poses a risk to the developing fetus and newborn. Genital herpes is common in the United States. Among 14- to 49-year-old females, the prevalence of HSV-2 infection is 15.9%. However, the prevalence of genital herpes infection is higher than that because genital herpes is also caused by HSV-1 1. Because many women of childbearing age are infected or will be infected with HSV, the risk of maternal transmission of this virus to the fetus or newborn is a major health concern. This document has been revised to include that for women with a primary or nonprimary first-episode genital HSV infection during the third trimester of pregnancy, cesarean delivery may be offered due to the possibility of prolonged viral shedding.