Exposed to Fifth Disease While Pregnant? What to Know

What does the evidence say about fifth disease exposure during pregnancy?

1. A known exposure does not establish maternal infection; blood tests can show whether a person is immune, susceptible, or has a recent infection. 1
2. Fifth disease spreads mainly through respiratory secretions, and parvovirus-specific IgM and IgG testing can help assess infection. 2
3. Pregnant people with acute infection need close obstetric follow-up, with serial ultrasounds used to watch for fetal complications such as hydrops fetalis. 3
4. Maternal parvovirus B19 infection can lead to fetal anemia and hydrops, while most pregnancies have satisfactory outcomes; confirmed infection should be referred to maternal-fetal medicine. 4
5. MotherToBaby reports that most people infected during pregnancy deliver healthy babies, while fetal infection can sometimes cause anemia, myocarditis, or hydrops. 1

Is fifth disease exposure safe in each trimester?

• First trimester. In the first trimester, exposure alone does not prove parvovirus B19 infection. Contact your prenatal clinician about blood testing, especially after close contact or symptoms. If testing suggests a recent infection, your care team can decide whether additional fetal monitoring is appropriate.
• Second trimester. In the second trimester, exposure still differs from confirmed infection. A recent maternal infection can occasionally lead to fetal anemia or hydrops, so your clinician may arrange specialist follow-up and serial ultrasound monitoring. Do not infer fetal harm from exposure alone or from the absence of a rash.
• Third trimester. In the third trimester, report a known exposure or compatible illness to your prenatal clinician. Confirmed infection can still warrant monitoring, although many pregnancies have healthy outcomes. The absence of symptoms does not rule out infection, and a rash does not establish when exposure occurred.