CMV: Common questions

June 3, 2020

Q. What Is CMV?
A. Cytomegalovirus, also called CMV, is a kind of herpesvirus. There are many kinds of herpeviruses. Some are sexually transmitted diseases, some can cause problems like cold sores and some can cause infections like CMV. CMV is the most common virus passed from moms to babies during pregnancy.

Q. Who gets CMV?
A. CMV is a common viral infection that most of us get at some point in our lives, often during childhood.

Q. Is CMV dangerous during pregnancy?
A. It can be. CMV can pass to your baby at any time during pregnancy, labor and birth and even while breastfeeding. According to Mother to Baby, the chances of passing CMV to your baby is between 30% and 50%. About 1 in every 200 babies is born with CMV. Most babies born with CMV don’t have health problems caused by the virus. But CMV can cause problems for some babies, including microcephaly. This is a birth defect in which a baby’s head is smaller than expected, compared to babies of the same sex and age.

Q. How can you protect yourself from CMV?
A. Here are some things you can do:

• If you’re around children, wash your hands well after being in contact with their body fluids. For example, wash your hands after changing diapers, wiping noses and picking up toys.
• Carefully throw away used diapers and tissues.
• Don’t kiss young children on the mouth or cheek.
• Don’t share food, glasses, cups, forks or other utensils with young children or with anyone who may have CMV.
• If your partner has CMV, use a latex condom during sex.

Q. How do you know if you have CMV?
A. Most people with CMV have no signs or symptoms. But some may have a sore throat, fever and swollen glands, or feel tired all the time (fatigue). Tell your health care provider if you think you may have CMV.

Q. Can you find out if you have or had CMV?
A. Yes. You can have a blood test to check for CMV. If you’re not pregnant and you’ve recently been exposed to CMV, you provider can do a blood test to confirm when it’s OK for you to get pregnant. You also can get tested during pregnancy. If your blood test is positive for CMV, your provider can check your baby for the virus using amniocentesis. Amniocentesis is a prenatal test that can diagnose certain health conditions in your baby.

Q. How are babies with CMV treated?
A. If your baby has signs of CMV, she may be treated with antiviral medicines (medicines that treat infections caused by a virus). Scientists are working to develop a vaccine for CMV. They’re also looking for other ways to prevent babies from being born with CMV.

For more information about CMV and other infections during pregnancy, visit