Cytomegalovirus (CMV) is type of common virus. There are different types of infection you can get from CMV:

• Primary infection. This is when you get CMV for the first time. Once you've had the virus, it stays dormant in your body and may become active again later on.
• Secondary infection. This is when you've had CMV before and it becomes active again. When this happens, your body already has antibodies to help keep the virus in check.

If you get either infection during pregnancy, the fetus may also get CMV.

CMV can spread through contact with certain body fluids. Examples are saliva, urine, tears, blood, semen, and breast milk. It can also spread though blood transfusions and organ transplants.

During pregnancy, CMV can pass through the placenta to the fetus. Newborns can be exposed to CMV from contact with body fluids during birth or later through infected breast milk.

Although CMV can be passed through breast milk, in healthy babies the benefits of breastfeeding may outweigh the risks. And you may have options for freezing and then thawing breast milk in order to reduce the risk of passing CMV to your newborn. Talk with your doctor about what they recommend.

Most adults and babies don't have symptoms of CMV.

If you do have symptoms, they can be similar to those of an Epstein-Barr virus infection, which is the main cause of mononucleosis (mono).

Adult symptoms may include:

• Fever.
• Chills.
• A sore throat.
• Swollen glands.
• Body aches and fatigue.

Symptoms in a fetus may include:

• Calcium deposits in the belly, liver, or brain.
• An enlarged liver and spleen.
• Abnormal-looking bowel or kidneys.
• Fluid buildup.
• Enlarged parts of the brain.
• A smaller than normal head.
• Reduced growth overall (growth restriction).

Babies born with CMV may not have health problems at birth. They may have health problems that develop later in life.

Adults and newborns can be diagnosed using:

• Blood tests.
• A urine test, saliva test, or tissue sample.

A fetus can be diagnosed using:

• Ultrasounds.
• A sample of amniotic fluid (amniocentesis).

Treating CMV can help manage symptoms for you and your baby. Treatment may include using antiviral medicine. You may get a referral to a maternal-fetal medicine specialist for treatment.

When you have CMV in pregnancy, you can care for yourself by:

• Managing your symptoms. For example, take over-the-counter acetaminophen (Tylenol) for a fever.
• Going to counseling if you're feeling distressed or if you need emotional support.
• Joining a consumer-led support group. Some examples include the National CMV Foundation in the United States and CMV Canada in Canada.

To help prevent the spread of CMV:

• Always wash your hands with soap and water. Remember to wash after going to the bathroom, changing diapers, feeding children, wiping a child's nose or mouth, or touching toys.
• Don't kiss young children on the mouth.
• Don't share forks, spoons, cups, or food with young children.