Is preeclampsia an infectious disease?

Background. Studies have suggested a strong paternal factor in the etiology of preeclampsia. If preeclampsia is caused by an infectious agent transmit ted by the woman's partner, seronegative women who may experience primary i nfection in pregnancy should be at increased risk of preeclampsia as compar ed to previously infected women. The aim of this study was to assess the im pact of being seronegative for some viruses transmitted by close contact on the risk of developing preeclampsia. Methods. Nine hundred and seventy-eight women were randomly drawn from a ba sic study population of 35,940 pregnant women in Norway. A serum sample dra wn at the first antenatal visit was analyzed for specific IgG antibodies ag ainst herpes simplex virus type-2, cytomegalovirus and Epstein-Barr virus. For comparison, antibody status against Toxoplasma gondii was also assessed . Information on preeclampsia in pregnancy was obtained through linkage to the Medical Birth Registry of Norway. Results. Thirty-three (3%) women developed preeclampsia. The risk of develo ping preeclampsia seemed to be increased for women who were seronegative fo r the viruses studied. Seronegativity for Toxoplasma gondii did not show su ch a pattern. Interpretation. Women who are seronegative for antibodies against viral age nts transmitted through close contact seem more likely to develop preeclamp sia. This finding indicates that women who are seronegative to such agents may acquire primary infection in pregnancy, and subsequently be at increase d risk of preeclampsia. This hypothesis could represent a new approach to t he causes of preeclampsia, and encourage search for yet unidentified microb es as a possible causal factor.