Department of Pediatrics

CMV and Pregnancy


Frequently Asked Questions


Find the answers to your most frequently asked questions, or you can choose to download or print the National CMV Registry brochure in English or Spanish.


CMV and Pregnancy


Item Term
I'm thinking about becoming pregnant. Is there any test that can be done to show if I could be at risk for catching CMV?

Item Definition

Every woman of childbearing age should consider knowing her CMV status. Prior to becoming pregnant or early as possible during your pregnancy, consult your doctor to have a blood sample drawn and a CMV antibody test performed. If results are positive for CMV IgG antibody, you most likely have had CMV sometime before in your lifetime. A positive CMV IgG antibody result rarely means you are experiencing a new infection. A CMV IgM antibody test may help distinguish between a new or recent infection (IgM-positive) or an old infection (IgM-negative). Since most women may have a positive CMV IgM antibody response for at least 4 to 6 months, and some for as long as a year or more, if you have both CMV IgG antibody and CMV IgM antibody, then a third test, called the CMV IgG avidity index may be helpful in determining if your CMV infection occurred less than 4 months ago. And depending on the time during your pregnancy your blood was drawn, the CMV IgG avidity index may help determine if your CMV infection occurred during your pregnancy or just prior to your pregnancy. If, on the other hand, the original CMV IgG antibody test result is negative, you have no CMV antibodies; and thus, you are susceptible to catching the virus for the first time. In this case, it is wise to practice the precautionary measures (see Precautions and Preventions) that may reduce your risk of catching CMV during your pregnancy