Pregnant women who have already been exposed to CMV prior to pregnancy will have CMV antibodies in their blood and there is a very small chance that a CMV reactivation would infect their unborn child.
Infection during one pregnancy does not increase the risk for subsequent pregnancies. Women who have experienced a primary CMV infection during pregnancy, a fetal loss due to CMV, or a newborn with congenital CMV should discuss these factors with their doctor and consideration should be given to waiting for at least 12 months before becoming pregnant again.
Most experts recommend that women wait until their CMV IgM antibody levels decline to an undetectable level and their CMV IgG avidity index climbs to a high favorable percentage. This would indicate that the primary infection has resolved itself and that there is minimal risk of CMV transmission to the new baby.