A new study suggests that pregnant women who spend time with young children have an increased risk of infection with parvovirus B19, which has been linked previously to an increased risk of miscarriage. Researchers at the Statens Serum Institut in Copenhagen, Denmark, tested the blood of nearly 31,000 pregnant women to collect data. The study found that 65 percent of women tested had contracted parvovirus B19 previously, rendering them immune to further infection, but that susceptible pregnant women were at significant risk of infection during epidemics, with the risk among women with other children being up to seven-times higher than among women without children. Authors note that women who worked with children in daycare settings were at even greater risk of infection, and that the rate of miscarriage among women infected with parvovirus B19 during pregnancy is about 1 percent to 9 percent. The study is in The Journal of the American Medical Association (1999;281:1099-1105).