Pregnant women should avoid new CMV infection

Dear Doctor K: At a recent pregnancy checkup, my doctor said something about cytomegalovirus. What is that, and what does it have to do with pregnancy?

Answer: Cytomega - lovirus (CMV) i s one of eight members of t he family of human herpes-viruses . The first two members are the viruses that cause “herpes” sores of the mouth, genitals and other areas.

All of the herpes-viruses cause a lifelong infection. Once you are infected with CMV, it remains in your body, generally causing no trouble. Up to 85 percent of adults in the United States have been infected. The virus can pass from person to person through body fluids such as blood, urine or sa l iva . Women ca n pass CMV to t hei r unborn babies in the womb, in vaginal secretions during delivery and in breast milk after birth.

In most healthy adults and children, a new infection with CMV results in only mild and temporary symptoms. In fact, a new infection often is “silent,” causing no symptoms at al l . Adults get seriously il l from CMV primarily when their immune systems become weakened by disease (such as HIV infection) or treatments that suppress the immune system.

But CMV can be serious, a nd even fatal, for newborn babies. That’s why, if you are pregnant, your doctor may want to test you for CMV.

When a pregnant woman becomes newly infected with CMV duri ng pregnancy, there is a 40 percent chance her baby will become infected. In contrast, less than 2 percent of babies born to mothers who were infected with CMV before they beca me pregnant a re infected. And their problems tend to be less severe.

CMV infection in newborns whose mothers were infected during pregnancy can cause serious disability.

The effects of CMV in newborns can vary greatly. Some babies may die from the infection , but others may have no longlasting effects.

Newborns with CMV are likely to be born premature and at a low birth weight. They may be born with a small brain or other nervous system disorders that can cause seizures, deafness, mental disability or death. CMV ca n cause the liver a nd spleen to enlarge, liver abnormalities that cause yellowing of the skin and eyes, and blood disorders.

Parents, including expectant mothers, can become infected from their children, though. CMV does not spread easily. Still, someone like you who is pregnant should be careful if you have young kids in the house. The following t ips may reduce your risk of getting CMV:

Wash your hands often with soap and water, especially after changing diapers.

Don’t kiss young children under age 5 or 6 on the mouth or cheek. Instead, kiss them on the head or give t hem a big hug.

Don’t share food, drinks or utensils with young children.

Don’t put a child’s pacifier in your mouth. (Seem obvious? I’ve had at least one patient do it thoughtlessly.)

These few precautions can protect you and your baby from becoming seriously ill from a virus that usually causes no harm.