Cytomegalovirus (CMV) is a virus that originates from the same group that causes herpes infection, chickenpox, and cold sores. The virus may infect several people but rarely causes long-term problems. Women who are infected by CMV in pregnancy may transmit the infection to their babies (congenital CMV), potentially causing neonatal health problems. It is estimated that around 1–4% of all pregnant women may get affected with primary CMV infection (1).
Read this post to learn more about the causes, symptoms, risks, treatment, and prevention of CMV infection during pregnancy.
What Is Cytomegalovirus Infection?
Cytomegalovirus infection is a common perinatal infection and could also lead to a CMV infection in babies due to maternal transmission (2) (3). Similar to other herpes viruses, the CMV shows characteristics of latency and reactivation. It means once you get infected, the virus stays dormant in the body forever.
The immune system keeps the virus under check, preventing its multiplication. Certain conducive factors, such as immunodeficiency or immunosuppression, may cause the virus to multiply rapidly beyond the immune system’s control. It could lead to re-emergence of symptoms and related problems (4).
What Are The Symptoms Of CMV Infection During Pregnancy?
- Sore throat
- Swollen lymph nodes
Rarely occurring symptoms include:
What Causes CMV Infection?
The CMV infection spreads by coming into close contact with a person with an active infection. It may be passed during sexual activity or when you come in contact with infected body fluids such as saliva, urine, blood, tears, urine, or stool (1).
Active infection means:
- Someone has a primary or first-time infection with CMV.
- A reactivated infection due to a weakened immune response.
- You get infected with a different strain of CMV.
What Are The Risks Of CMV Infection During Pregnancy?
- Contact with saliva, urine, or stools: Young children are the major source of cytomegalovirus, and most may not usually show significant symptoms. Therefore, parents of young children are at a higher risk of contracting the infection. You may catch the virus if you do not wash your hands after wiping your child’s nose, cleaning their mouth, or changing their diapers.
- Sexual activity with a non-monogamous partner: If you are sexually active during pregnancy and your partner has multiple sex partners, you may be at risk of contracting CMV infection. The virus is transmitted through bodily fluids, including semen.
- Reactivation due to poor immunity: If you had CMV infection in the past, poor immunity due to pregnancy-related factors, other diseases, or certain medications may reactivate the latent virus in the body.
How Is CMV Diagnosed During Pregnancy?
Cytomegalovirus is rarely diagnosed as the infected persons show very few or no symptoms. It is not a part of routine screening during pregnancy. The presence of the virus may be diagnosed by (8) (9):
- Testing for antibodies (the antibodies developed during the infected stage remain lifelong) in a blood sample with a repeat test after two weeks for confirmation.
- The virus may be cultured from throat swabs or tissue or urine samples.
Once a pregnant woman tests positive for CMV, the fetus is tested by:
- Amniocentesis (drawing a sample of amniotic fluid) to look for the presence of the virus.
- Further evaluation may be carried out using ultrasound examinations to identify fetal abnormalities related to the infection. Reduced amniotic fluid, restricted fetal growth, and central nervous system involvement (microcephaly), chorioretinitis and periventricular calcifications. d pneumonitis, hepatosplenomegaly and thrombocytopenia may indicate possible fetal infection.
How Is CMV Infection Treated During Pregnancy?
If you have CMV infection with symptoms, you may consult a doctor who may provide you with medications for symptomatic relief. You may also observe other general practices observed during viral infection, such as adequate rest and fluids with a healthy diet.
Some treatment options are available, but no curative medication is specified. One study mentions using hyperimmune globulin (similar to antibodies) for pregnant women to prevent viral transmission to the fetus. Antiviral medications such as Ganciclovir and Valganciclovir have shown some favorable results in the treatment of the infection. These medications may also help avoid infection-related complications in the fetus, although evidence is limited (9) (10).
How To Prevent CMV Infection During Pregnancy?
There are currently no vaccines to prevent CMV infection. Cytomegalovirus usually spreads when you touch your nose or mouth after touching infected body fluids. CMV infection may be prevented if you maintain proper hygiene and adopt measures to avoid coming in contact with the body fluids of infected persons.
- Practice regular handwashing with soap and water.
- Regularly clean surfaces that may have body fluids on them.
- Wash your hands after cleaning your child’s nose or mouth.
- Wear gloves when changing a baby’s diapers.
- Do not share food, drinks, or utensils with other people, including your children, during pregnancy.
- Avoid sexual activity or kissing with new partners if you are not aware of their CMV status.
What Is The Risk Of CMV Transmission To The Fetus?
The risk of vertical transmission is lowest in the first trimester of pregnancy. In case the fetus acquires infection at this time, the risk of developing serious congenital malformations is highest. As pregnancy advances (third trimester), the risk of fetal transmission increases, but the odds of the baby having serious birth defects are less (4). This may be due to the increased passing of maternal antibodies to the fetus with advancing gestational age. Infection may also be passed through vaginal secretions during birth and via breast milk after that.
Is It Safe To Nurse A Baby If Tested Positive For CMV?
The virus may be present in breast milk, but the risk of infection is more in babies born preterm as they are deficient in the maternal antibodies that pass on to them during the later stage of fetal development or later in breast milk itself. Given the known benefits of breastfeeding, you should consult your doctor before you stop nursing your baby due to the infection (13).
Cytomegalovirus (CMV) infection is usually harmless and does not cause serious problems during pregnancy. It produces illness mostly in immunocompromised states and rarely in healthy adults as the virus stays dormant in them. Discuss with your healthcare provider if you wish to get tested for the virus. In case your child contracts the infection from you, regular monitoring of symptoms is required for early detection and appropriate therapy.
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- Cytomegalovirus (CMV) Infection.
- Vera Seidel et al. Intrauterine therapy of cytomegalovirus infection with valganciclovir: review of the literature.
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