Prediction of placental abruption by testing for C‐reactive protein and chlamydial antibody levels in early pregnancy

Objective Placental abruption may be a manifestation of acute and chronic inflammatory process. We wanted to assess the association of first‐trimester serum C‐reactive protein (CRP), Chlamydia pneumoniae antibodies, Chlamydia trachomatis antibodies or chlamydial heat‐shock protein 60 (CHSP60) antibodies to placental abruption. Design Retrospective case–control study. Setting University Hospital. Population A total of 181 women with subsequent placental abruption and 261 control women with normal pregnancy. Methods Serum samples collected at first trimester (mean 10.4 gestational weeks) were analysed for CRP levels, C. pneumoniae‐specific immunoglobulin G (IgG) and immunoglobulin A (IgA) antibodies and C. trachomatis‐specific IgG, IgA and CHSP60 antibodies. Main outcome measure Placental abruption. Results The levels of CRP showed no difference between the cases and the controls (median 2.35 mg/l [interquartile range {IQR} 1.09–5.93] versus 2.28 mg/l [IQR 0.92–5.01], not significant). C. pneumoniae‐specific IgG and IgA as well as C. trachomatis‐specific IgG, IgA and CHSP60 antibody frequencies were similar between the groups. There was no association between CRP levels and chlamydial antibodies. Conclusion These markers of inflammation in early pregnancy failed to predict subsequent placental abruption.