Toxoplasma prevalence among pregnant women in Norway: a cross-sectional study.

Infection by Toxoplasma gondii may lead to complications in the foetus if the mother suffers from primary infection during pregnancy. Previously infected women have produced toxoplasma-specific IgG antibodies. The most recent study on prevalence of toxoplasma IgG in the Norwegian pregnant population was conducted 20 years ago. The present study is part of a research programme initiated by the Norwegian Institute of Public Health. We aimed to update the knowledge regarding the prevalence of toxoplasma IgG among pregnant women in Norway. In this cross-sectional study, sera from 1922 pregnant women in Buskerud (992) and Sør-Trøndelag counties (930) in Norway were collected consecutively. The presence of toxoplasma IgG was identified by values ≥8 IU/mL using an ELISA test. The overall prevalence of toxoplasma IgG seropositivity was 9.3% (95% CI 8.1-10.7); Sør-Trøndelag 10.4% (95% CI 8.6-12.6) and Buskerud 8.3% (95% CI 6.7-10.2). There was no difference between the counties (p = 0.13), and the result did not differ from prevalences found in 1974 (12.1%) and 1994 (10.7%). We found a higher prevalence among women ≥40 years (OR 2.65, 95% CI 1.30-5.42). The prevalence of toxoplasma IgG among pregnant women in Norway is low and has been stable during the last decades.