Cytomegalovirus (CMV) is a common virus that infects persons of all ages, races, and backgrounds. Originally described as a rare cause of "cytomegalic inclusion disease," CMV is now known to cause a broad spectrum of illness in the fetus and newborn, with most infections being asymptomatic at birth. This article discusses the epidemiology and diagnosis of CMV infection in pregnant women, the fetus, and the newborn, including recent advances in antenatal diagnosis. In addition, the challenges of treatment and prevention of congenital CMV are explored.