Antiphospholipid antibodies increase the risk of pregnancy-induced hypertension and adverse pregnancy outcomes

Antiphospholipid antibody (aPL) is associated with thromboembolism. There is scant evidence of a relationship between the aPL profile and serious adverse pregnancy outcome. The aim of this study was to assess whether aPL measurements during early pregnancy were useful in predicting a serious adverse pregnancy outcome. In this prospective study, we measured aPLs, including lupus anticoagulant (LA), IgG, IgM, IgA anticardiolipin antibody (aCL), IgG, IgM phosphatidylserine-dependent antiprothrombin antibody, and IgG kininogen-dependent antiphosphatidylethanolamine antibody (aPE) during the first trimester in a consecutive series of 1155 women. The 99th percentile cut-off values in each aPL were determined using samples from 105 women who did not exhibit any pregnancy morbidity. We assessed the predictive risk of a serious adverse pregnancy outcome adjusted for confounding factors. We found that IgG aCL was asssociated with developing pregnancy-induced hypertension (PIH) (odds ratio 11.4, 95% CI 2.7–48); IgG aPE with PIH (8.3, 2.4–29), severe PIH (20.4, 4.5–91), and premature delivery (PD) (12.7, 3.1–50); and LA with PD (11.0, 2.8–44) and low birth weight (8.0, 2.1–31). The combinations of IgG aPE plus IgG aCL (17.5, 4.7–66.7) or IgG aPE plus LA (22.2, 5.4–909) measurements predicted severe PIH with 30.8% sensitivity and 99.2% specificity. We conclude that aPL measurements during early pregnancy may be useful in predicting adverse pregnancy outcome.