Cytomegalovirus During Pregnancy
The CDC (Centers for Disease Control and Prevention) tells us that about half of pregnant women in the US have never been infected with CMV but about 1% to 4% of them have a primary (or first) CMV (Cytomegalovirus) infection during their pregnancy. Many experience no symptoms. What makes it a concern is that the virus in the mother’s blood crosses over the placenta and infects the fetus’ blood.
Most babies with congenital (present at birth) CMV infection never have health problems. For those that do, it may be apparent at birth or develop later during infancy or childhood.
What is CMV?
CMV is a member of the herpes virus group that is characterized by the ability to remain dormant within the body over a long period. Infectious CMV may be shed in bodily fluids (urine, saliva, blood, tears, semen, and breast milk) intermittently, without any detectable signs and without symptoms.
There are two different types of infection: primary CMV and recurrent CMV infection. Primary infection can cause more serious problems in pregnancy than recurrent infection can. However, if a person’s immune system is seriously weakened in any way, the virus can become active and cause CMV disease.
Who is at risk for developing CMV?
- By 40 years of age, over half of all adults have been infected with CMV.
- It is more widespread in developing countries and in areas of lower socio-economic conditions.
- It is notably higher among the following risk groups:
- Babies in utero
- People who work with children
- Immune-compromised persons, such as organ transplant recipients and persons infected with human immunodeficiency virus (HIV)
How is CMV spread?
The transmission is not associated with food, water, or animals, but from person to person. The infection is spread through:
- Close, intimate contact with a person excreting the virus in their saliva, urine, breast milk or other bodily fluids
- Infants and children who are infected with CMV after birth may pass the virus in their urine and to parents, household members and other caregivers who have frequent contact with them through activities such as diaper changing, nose wiping, and feeding
- For pregnant women, the two most common exposures to CMV are through sexual contact and through contact with the urine of young children with CMV infection.
What are the symptoms of CMV?
Most children and adults who are infected with CMV do not develop symptoms, whereas others may experience the following symptoms three to twelve weeks after exposure:
- Swollen glands
- Feeling exhausted or run down
- Risks associated with contracting CMV during pregnancy
- 85-95% of babies who contract the CMV virus while in their mother’s womb will have no symptoms or complications at birth and the majority will not develop problems later in life.
- 10-15% of those at birth with no symptoms will go on to develop varying degrees of hearing and mental or coordination problems.
- Other potential complications include moderate enlargement of the liver and spleen, small red spots on the skin, problems with the eyes and seizures.
When CMV is transmitted at the time of delivery from contact with genital secretions or later in infancy through breast milk, these infections usually result in few, if any, symptoms or complications.
How is CMV diagnosed?
Most CMV infections are rarely diagnosed because the virus usually produces few, if any, symptoms. However, people who have had CMV develop antibodies to the virus which remain in their body for the rest of their life.
- A blood sample can test for the CMV antibody, followed by another blood sample within two weeks.
- The virus can also be cultured from specimens obtained from urine, throat swabs, and tissue samples. These tests are expensive and not widely available.
- Amniocentesis can be done to check fetal fluids or blood for signs of infection during pregnancy. Symptoms that could signify possible infection include low amniotic fluid levels, intrauterine growth restriction, and enlarged tissues in the brain.
- Once the baby is born, testing can be done by saliva, urine, or blood.
Currently licensed treatments that are effective against CMV infection have serious side effects, and are not approved for use in pregnant women. They have also not been shown to prevent CMV infection in the fetus. Scientists are working on CMV vaccines and are looking for other ways to prevent congenital CMV infection.
Transmission of cytomegalovirus is usually preventable because it is most often transmitted through infected bodily fluids that come in contact with hands and then are absorbed through the nose or mouth of a susceptible person. Hand washing with soap and water is effective in preventing the spread of CMV. People who interact with children should use safe hygiene practices including good hand washing and wearing gloves when changing diapers.
Dr. Jorge L. Gomez earned his Medical Degree in 1990 at Central Del Caribe University in Bayamon, Puerto Rico. Following residency in Obstetrics and Gynecology at Bronx-Lebanon Hospital center in the Bronx, NY (1990–1994), he completed additional fellowship training at New York University Medical Center NY, specializing in Maternal Fetal Medicine (1994-1996). After his fellowship in 1996 he joined South Florida Perinatal Medicine. Dr. Gomez is Board certified in OBGYN and Maternal Fetal Medicine. From 2003–2007 He was a reviewer for the American Journal Of Obstetrics and Gynecology.