slapped cheek disease and pregnancy

Last reviewed 03/2022

  • erythrovirus (formerly parvovirus) type B19 is the cause of 'fifth disease' (also known as slapped cheek disease and erythema infectiosum)
  • between 50-60% of adults have been infected previously with parvovirus but the infection has been asymptomatic
  • infection with erythrovirus B19 is uncommon in pregnancy
  • the majority pregnant women with parvovirus infection have normal, healthy babies
  • but there has been fetal death and occasional hydrops fetalis associated with the infection (1)
  • there is no routine screening test for parvovirus B19 in pregnancy
  • the risk of intrauterine transmission increases with gestational age
    • < 4 weeks - 0%
    • 5-16 weeks - 15%
    • > 16 weeks - 25-70% (2)
  • there is a risk of fetal death in about 10% of cases
    • adverse fetal/neonatal outcomes associated with fetal infection include:
      • risk of adverse fetal/neonatal outcomes vary with respect to gestational age at the time of infection with parvovirus:
        • if parvovirus infection occurs in the first 20 weeks of pregnancy, the risk of miscarriage rises from the 5% that a woman who is not infected with the virus has, to 15%
        • if parvovirus infection occurs in weeks 9-20, as well as the 15% risk of a miscarriage, there is also a 3% risk your baby will develop non-immune hydrops fetalis
          • hydrops fetalis is fatal in about 50% of cases
        • other possible of parvovirus infection include growth retardation, myocarditis/infarction, meconium peritonitis, placentomegaly, oedema, anaemia, rashes, thrombocytopaenia, leucopenia and respiratory insufficiency
        • fetal risk is greatest in the second trimester
    • usually these adverse effects tend to occur some 3-5 weeks after the onset of maternal infection (can be later too) (2)
    • if possible parvovirus infection has occurred in pregnency then:
      • check parvovirus serology
      • if positive test in the first 20 weeks of pregnancy, then regular ultrasound scans are indicated to monitor fetal growth and development - if fetal hydrops develops then intrauterine transfusion may be indicated
  • there is an approximate 1% risk of congenital abnormality (1)

Reference: