Cytomegalovirus (CMV) occurs in 0.2 % to 2.2 % of all live births and is the most common cause of intrauterine infection and the leading infectious cause of sensorineural hearing loss and mental retardation. This article reviews literature that relate to the pathogenesis, diagnosis, and treatment of this disease for pregnant women and their fetus. Primary maternal CMV infection during pregnancy has a much higher rate of mother-to-fetus transmission and causes symptoms at birth and long-term disability than nonprimary infection. In addition, some research has shown that children with congenital CMV infection following first-trimester maternal infection are more likely to have severe sequelae. The prenatal diagnosis of fetal CMV infection includes serological testing (IgM detection and IgG avidity assay), amniocentesis, and ultrasound examination. The combination of the presence of CMV IgM antibodies and low CMV IgG avidity, along with maternal or fetal symptoms is used for the diagnosis of a primary maternal infection. Amniocentesis should be complemented until approximately 20-21 weeks of gestation to increase the sensitivity. Because ultrasound abnormalities are only found in less than 25 % of infected fetuses, ultrasound is as a relatively poor predictor of symptomatic congenital infection. CMV hyperimmunoglobulin also may be considered when the pregnant women are confirmed as primary CMV infection with low IgG avidity and amniotic fluid is found to contain CMV or CMV DNA. There is no consensus on the benefit of prenatal administration of ganciclovir into the umbilical vein.