Did You Know ?

Public health officials estimate that the annual cost of caring for children with congenital CMV is $1.86 billion.

What Are the Consequences of CMV for My Baby?

The consequences of CMV in your baby depend on when the infection occurs. The risk of viral transmission to your baby is greatest if you contract CMV in your third trimester, but the risk of severe injury to your baby is greatest if you contract CMV in your first trimester. Results of a fetal CMV infection range from virtually non-existent to premature death. Further, some infants do not show consequences of the infection until a few years after birth.

If you have CMV and know that your baby is also infected, you and your doctor should discuss the types of problems that your baby may have. If your doctor believes that your baby will suffer extreme consequences, you should be prepared to discuss termination of the pregnancy.

Overall, about 1% of infants born in the U.S. each year (40,000 infants) are born with CMV infections. About 3,000 to 4,000 of these infants show symptoms when they are born, and 4,000 to 6,000 others show signs of neurological or developmental problems in their first years of life.

The most common consequences of CMV infection in infants include:

  • enlargement of the liver and spleen;
  • calcifications in the brain;
  • jaundice (yellowing of the skin);
  • low birth weight;
  • microcephaly (small head);
  • chorioretinitis (eye infection);
  • hearing loss; and
  • low platelet count (blood cells that help form clots and prevent excess bleeding).

 

Approximately 30% of severely infected infants do not survive. Infants who suffer from edema or hydrops (excess fluid in the lungs or abdomen) usually have severe heart or liver dysfunctions and are at extreme risk. Eighty percent of surviving infants suffer from severe neurological complications, eye abnormalities (chorioretinitis), or hearing loss. Infants with a damaged central nervous system (such as small head and brain, dilation of the cerebral ventricles, brain calcification) run a risk of being born mentally retarded or with vision or hearing problems. Fortunately, 85 to 90% of infants do not suffer from serious infections. Of these, however, 10 to 15% develop hearing loss, chorioretinitis, or dental defects within the first two years of life.

Imaging to Identify Severity

The most effective way for your doctor to determine if your baby is infected is through amniocentesis, which tests the amniotic fluid. While this test is quite accurate at diagnosing CMV, it cannot determine the severity of the infection. For this, your doctor conducts an ultrasound, which allows him to see to what extent the virus has interfered with your baby's development.

The most serious problems associated with CMV appear on an ultrasound image, including:

  • small head (microcephaly);
  • enlargement of fluid-filled chambers in the brain (ventriculomegaly);
  • calcifications, either in the brain or body;
  • severe fluid collections in the lungs or abdomen (edema or hydrops);
  • inhibited growth;
  • poor heart function or blockage in the heart; and
  • low volume of amniotic fluid.

You should be aware that an ultrasound might appear normal early in a fetal infection. Therefore, if the amniocentesis confirms that your baby is infected but your ultrasound does not show abnormalities, your doctor will perform additional ultrasounds as you progress through your pregnancy.