Reported maternal-to-fetal rates of primary cytomegalovirus (CMV) infection during pregnancy have been between 30% and 50%. The highest rate of symptomatic congenital infection and sequelae occurs in about 25% of infected infants born of mothers with a primary infection during pregnancy. Symptomatic infants demonstrate a constellation of clinical features that reflect placental dysfunction and probable viral infection of the central nervous system of the fetus. In the United States, we estimate that about 8000 affected infants are born each year. Two options may be available to prevent or treat maternal CMV infection during pregnancy, especially for women with exposure to young children in the home. The first is hygienic intervention. Two studies support the simplicity, harmlessness, and effectiveness of hygienic intervention to prevent child-to-mother transmission of CMV among high-risk pregnant women who know they are susceptible. The second is CMV immunoglobulin. A meta-analysis of 2 clinical trials showed an efficacy of 50% if immunoglobulin is given to pregnant women who have acquired a primary CMV infection during pregnancy. These results mean that seronegative pregnant women have options to prevent fetal infection.