Parvovirus B19 infection in pregnancy.

OBJECTIVES: (1) To review the effects of parvovirus B19 on the pregnant woman and fetus, and (2) to discuss the management of women who are exposed to, who are at risk of developing, or who develop parvovirus B19 infection in pregnancy. OUTCOMES: Maternal outcomes of parvovirus B19 including erythema infectiosum, arthropathy, anemia, and myocarditis. Fetal outcomes including spontaneous abortion, congenital anomalies, hydrops fetalis, stillbirth, and long-term effects. EVIDENCE: MEDLINE search from 1966 to January 2002 for articles relating to parvovirus B19 infection, using key words "parvovirus" and "pregnancy," and guidelines of professional organizations including the American College of Obstetricians and Gynecologists. VALUES: The evidence obtained was reviewed and evaluated by both the Maternal Fetal Medicine and Infectious Diseases Committees of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and recommendations were made according to guidelines developed by the Canadian Task Force on the Periodic Health Examination. RECOMMENDATIONS: 1. Pregnant women exposed to, or who develop symptoms of, parvovirus B19 infection should be assessed to determine if they are susceptible to infection (nonimmune) or if they have a current infection, by determining their parvovirus B19 IgG and IgM status. (II-2A) 2. If parvovirus B19 IgG is present and IgM is negative, the woman is immune and can be reassured that she will not develop infection and that the virus will not adversely affect her pregnancy. (II-2A) 3. If both parvovirus B19 IgG and IgM are negative (and the incubation period has passed), the woman is not immune and has not developed the infection. Although she may wish to minimize further exposure, leave from the workplace is controversial and is not routinely recommended. Further studies are needed in this area. (III-B) 4. If a recent parvovirus B19 infection has been diagnosed in the woman, then referral to an obstetrician or a maternal-fetal medicine specialist should be considered (III-B). The woman should be counselled regarding risks of fetal transmission, fetal loss, and hydrops. Serial ultrasounds should be performed up to 8 to 12 weeks after infection to detect the development of hydrops (III-B). If hydrops develops, referral to a maternal-fetal medicine specialist should be made and consideration should be given to fetal blood sampling and intravascular transfusion (II-2B). VALIDATION: These guidelines have been reviewed and approved by the Maternal Fetal Medicine and Infectious Diseases Committees of the SOGC, and the Council of the SOGC.