Cytomegalovirus: What Pregnant Women Need to Know About CMV

What Is Cytomegalovirus (CMV)?

Cytomegalovirus is a very common virus that affects people of all ages and most people will be infected during their lifetime. About one out of every 200 babies is born with congenital CMV; meaning it was passed to them during pregnancy from their mother through the placenta. Most babies do not show signs of infection or have long term health problems.

What Are the Symptoms of Congenital CMV?

Some newborns may have signs at birth like rash, jaundice, small head size, small for their gestational age, an enlarged liver and/or spleen, brain abnormalities or hearing loss. These signs can look similar to other newborn illnesses. Children born with CMV can develop hearing loss, vision problems and developmental delay. Although most babies with congenital CMV do not have signs at birth, they can still develop problems later in childhood like hearing loss.

How Is CMV Spread?

CMV can be present in all body fluids and spread through contact with saliva, urine, blood, semen, cervical secretions and breast milk. Human CMV is not spread through mosquitos, ticks or other animals. If a pregnant mother becomes infected or re-infected with CMV during pregnancy, the virus can infect the unborn child. Babies, children or adults who acquire CMV after birth generally do not have any serious or long term problems unless they are immunocompromised.

What Can I Do for My Unborn Baby?

There is no vaccine for CMV currently, so prevention of CMV infection during pregnancy is important. Pregnant women can lessen their risk of becoming infected or re-infected with CMV by avoiding contact with body fluids of others like saliva and urine.

Other children in the family can acquire CMV while in school and daycare and pass this infection to their pregnant family member or friend. Therefore, pregnant women should avoid sharing food, utensils or cups, putting pacifiers in their mouth and should wash their hands after contact with any body fluids like after changing diapers.

Currently, all newborn babies are not universally tested for CMV. It’s important for newborns with signs of congenital CMV or those who fail their newborn hearing screen be tested within the first few weeks of life. 

A mother who has CMV should not stop breastfeeding her baby since the benefits of breastfeeding outweigh the risks of passing CMV to their baby after birth.  

It’s also important to clean potentially contaminated surfaces. When choosing a cleaner, make sure it is certified by the EPA for effectiveness against CMV on household surfaces.

For more information on CMV, visit the Centers for Disease Control and Prevention website.