Association of raised titres of antibodies to <i>Chlamydia pneumoniae</i> with a history of pre‐eclampsia

Abstract

OBJECTIVE: To establish the prevalence of Chlamydia pneumoniae (C. pneumoniae) infection in a pregnant UK population and to investigate whether C. pneumoniae infection is more common in women with a previous history of pre-eclampsia. DESIGN: Prospective study. SETTING: Academic Hospital. POPULATION: Ninety-one pregnant women (54 parous and 37 nulliparous) at 16-22 weeks of gestation were studied. Of the parous women, 32 had a previous history of pre-eclampsia. METHODS: Peripheral blood was drawn for C. pneumoniae antibodies between 16-22 and 28-40 weeks of gestation. C. pneumoniae antibodies were measured using a solid-phase enzyme immunoassay. According to pregnancy outcome, women were categorised into normal, gestational hypertension and pre-eclampsia groups. MAIN OUTCOME MEASURES: Serum levels of IgG, IgA and IgM C. pneumoniae antibodies. RESULTS: Prevalence of seropositivity to C. pneumoniae was 77%. Parous women had significantly higher levels of IgA and IgM C. pneumoniae antibodies than nulliparous women (P < 0.04). Parous women with previous pre-eclampsia were found to have higher levels of antibodies than parous women with a normal obstetric history (P< or = 0.003). There was no difference in the antibody levels in women with different pregnancy outcomes. CONCLUSIONS: The longitudinal data do not indicate an association between C. pneumoniae infection and pre-eclampsia. However, the subgroup analysis of parous women demonstrated raised C. pneumoniae antibodies in the women with previous pre-eclampsia, and therefore suggests that there may be an association between C. pneumoniae and the disease in this group.