Cytomegalovirus, commonly referred to as CMV, is a member of the herpes virus family. It is common and typically harmless to the general population – between 50 and 80 percent of people in the United States have had a CMV infection before the age of 40. Once CMV is in a person’s body, it stays there for life and can reactivate.
CMV is the most common viral infection that infants are born with in the United States. Approximately 1-4 percent of uninfected women have a primary (or first) CMV infection during a pregnancy, and about 40 percent of women who become infected with CMV for the first time during pregnancy pass the virus to their babies.