What Is Cytomegalovirus?

Pregnant woman

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Pregnancy is a time for excitement and preparation, as well as caution and hypervigilance. You want to do everything to keep yourself and your growing baby safe, and that includes staying free of disease. One such disease to avoid is cytomegalovirus (CMV).

CMV, a common virus, can pass from the pregnant individual to their growing baby and cause issues, such as birth defects. "Although CMV is very common and rarely causes illness, the congenital form of the virus can be problematic," says Sandra El Hajj, N-MD, a health professional specializing in preventive and global health.

Anyone can become infected with CMV at any time, and it's likely that you already have been. Most people don't even know that they have CMV. The main concern is trying to make sure you don't get infected with this virus during your pregnancy, and you can take preventative measures towards this to help protect your baby. Let's dive more into what CMV is, how it's treated, and what you can do to prevent it.

What Is Cytomegalovirus (CMV)?

CMV is a common virus that is passed through bodily fluids, usually from coming into contact with children through diaper changes, breastfeeding, or other routine care.

Often, there are no symptoms. "Most people by the age of 40 have been infected, yet don't know," says Kecia Gaither, MD, MPH, FACOG, a double-board certified physician in obstetrics and gynecology and maternal-fetal medicine, and the director of perinatal services at NYC Health+ Hospitals/Lincoln in the Bronx. Occasionally, symptoms such as fever, fatigue, sore throat, or swollen glands may present in those with compromised immune systems.

CMV is a concern during pregnancy because it can pass through the umbilical cord and infect your fetus. This is known as congenital CMV, and it can cause serious problems for your baby. Babies born with CMV are at an increased risk of birth defects such as hearing or vision loss, intellectual disabilities, or seizures.

Congenital CMV is more likely if you are infected while you are pregnant, especially if it is the first time you have been infected. Avoiding becoming infected during pregnancy is most important when it comes to keeping your baby safe.

You can protect yourself from CMV infection during pregnancy by avoiding coming into contact with bodily fluids. "This is especially true when it comes to the saliva or urine or young children," says Dr. El Hajj. If you normally hold your toddler's pacifier in your mouth, sip from their sippy cup, or kiss them on the mouth, you may want to make some adjustments now that you have another baby on the way.

If you come into contact with body fluids such as breast milk, semen, urine, or blood, be sure to wash your hands immediately afterward. Since CMV tends to pass most easily through babies' or children's bodily fluids, be extra-mindful of your hygiene when you are changing diapers or patching up a boo-boo.

How Is CMV Diagnosed?

CMV can be diagnosed with a blood test. However, blood tests are not routinely recommended during pregnancy. A CMV diagnosis does not necessarily mean that your baby will become infected or suffer from birth defects even if they are.

Your provider may test your newborn for CMV if they are born with a small head size or have seizures, a rash, or other health problems at birth. If your baby shows signs of a possible CMV infection, saliva or urine tests are recommended instead of a blood test.

How Do You Treat CMV?

There is no cure for CMV, but there are medications that can help manage symptoms. "CMV stays in the body for life," notes Dr. Gaither. Healthy adults who do not have any symptoms do not generally need to be treated.

Adults with compromised immune systems or babies with CMV may be given an antiviral medication called valganciclovir. Valganciclovir may improve babies' hearing and reduce the occurrence of developmental problems. But it may have serious side effects and it should only be used for babies who have CMV.

How Can CMV Impact My Pregnancy?

You won't necessarily know whether you contract CMV while you are pregnant. The best thing you can do to protect your baby is to reduce the chances of that happening.

Avoid sharing things like utensils or toothbrushes with other children in your home. Wash your hands frequently and especially after coming into contact with a child's urine, such as during a diaper change, helping your child wipe, or cleaning up after an accident. You may also want to keep your kisses on your child's cheeks or forehead while avoiding kisses directly on the mouth.

Take extra caution if you come into contact with bodily fluids regularly, such as if you work in a healthcare setting or at a daycare or preschool.

A Word From Verywell

You can pass CMV to your baby in-utero, which could potentially lead to developmental issues including hearing loss, vision loss, seizures, or developmental delays.

CMV is a common virus that most people do not even know they have. It's best to try to avoid becoming infected for the first time or getting infected a subsequent time during your pregnancy. The best way to protect your baby from congenital CMV is to avoid coming into contact with bodily fluids; and if you do, to wash your hands immediately after.

If you have any questions or concerns about CMV, don't hesitate to reach out to your OB/GYN or healthcare provider.

3 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Cytomegalovirus (CMV) and Congenital CMV Infection. Centers for Disease Control and Prevention.

  2. CMV Fact Sheet for Pregnant Women and Parents. Centers for Disease Control and Prevention.

  3. About Cytomegalovirus (CMV). Centers for Disease Control and Prevention.

By Elisa Cinelli
Elisa is a well-known parenting writer who is passionate about providing research-based content to help parents make the best decisions for their families. She has written for well-known sites including POPSUGAR and Scary Mommy, among others.