[Prevalence of anti-human parvovirus antibody in pregnant women].

Human parvovirus B19 (B19) has been shown to be associated with erythema infectiosum. Recently, it was reported that when a pregnant woman is infected with B19, the fetus in her uterus sometimes becomes hydropic and results in a stillbirth. But no epidemiologic study of pregnant women in Japan has been performed yet. We have established an in vitro propagation system of B19 virions and an assay system for detecting anti-B19 antibody by indirect immunofluorescence (IF) staining. We examined the positive rate of anti-B19 antibody among 337 normal blood donors, 329 normal pregnant women, 23 early aborted women and 24 non-immune hydrops fetalis cases by IF staining. The positive rate for anti-B19 IgG among normal blood donors increased with age. It was 22% aged 21 to 30, 44% aged 31 to 40, 65% aged 41 to 50, and 76% aged 51 to 60, respectively. Anti-B19 IgG was detected in 33% of 329 of normal pregnant women. The anti-B19 IgG positive rate was 26% in pregnant women in their twenties and 44% in those in their thirties. There was a significant difference between the two generations. The results show that more than half the women in their twenties and thirties risk B19-infection during pregnancy. Nine of twenty-three early aborted women were positive for anti-B19 antibody. Among six pregnant women who were positive for anti-B19 IgM, four delivered normal babies and the others aborted artificially or spontaneously. Anti-B19 IgG and IgM of twenty four non-immune hydrops fetalis (NIHF) were examined and four cases were found to be anti-B19 IgG positive.(ABSTRACT TRUNCATED AT 250 WORDS)