Fifth disease and pregnancy
Fifth disease is a childhood illness that about half of us come down with when we’re kids, making us immune to it as adults. It’s caused by parvovirus B19. It got its odd name many years ago when it appeared fifth in a list of what were considered the common causes of childhood rash and fever. Most often, it’s not a big deal in childhood, but it might be to a developing fetus if the mother contracts it during pregnancy.
Fifth disease is a common, usually mild illness spread through the air from an infected person’s cough or sneeze. In children, it causes a distinctive “slapped cheek” rash and, less commonly, a low-grade fever, headache, sore throat and joint pain. Infected adults are less likely to develop a rash, but often experience joint pain and swelling, sometimes with mild flu-like symptoms. Symptoms generally appear between 4 and 14 days after exposure.
Fetal infection is rare. However, when a fetus does become infected, the virus can disrupt its ability to produce red blood cells, sometimes leading to a dangerous form of anemia and heart problems. Serious consequences are more likely when a pregnant woman contracts the infection in the first 20 weeks of pregnancy.
To reduce the risk of infection, pregnant women should wash their hands thoroughly after touching tissues used by infected children and dispose of these tissues promptly. They also should avoid sharing drinking glasses or utensils with anyone who has or was exposed to the illness.
A pregnant woman who has been exposed to fifth disease should consult her provider promptly. Blood tests can determine susceptibility or help diagnose the illness. If she is infected, her provider monitors the pregnancy carefully for signs of fetal problems. There is no drug to treat the disease. The provider will most likely recommend repeated ultrasound examinations (weekly or every other week) for 8-12 weeks after the mother was infected. If ultrasound does not show any problems during this time, no further treatment is needed.
You can read questions and answers about this in the fact sheet written by the Organization of Teratology Information Specialists (OTIS).