Antibodies to β2-glycoprotein I and annexin V in women with early and late idiopathic recurrent spontaneous abortions

Abstract

Anti-phospholipid antibodies (APA) are heterogeneous group of autoantibodies that target phospholipid or phospholipid-binding proteins. APAs were previously shown to induce several thrombotic states, including idiopathic recurrent spontaneous abortion (RSA). Unlike the contribution of the classical lupus anticoagulant (LAC) and anticardiolipin antibodies (ACA), the contribution of anti-β2 glycoprotein 1 (β2GPI) and anti-annexin V antibodies to RSA risk remain poorly understood. We assessed anti-β2GPI and anti-annexin V IgM and IgG antibodies as RSA risk factors for RSA in 172 Tunisian women with >3 consecutive idiopathic pregnancy losses, together with 173 matched control women. The prevalence of anti-β2GPI IgG (P=0.41, OR=1.64) and IgM (P=0.50, OR=1.70) were comparable between cases and controls. Higher anti-annexin V IgG (P=0.02, OR=5.28), but not IgM (P=0.25, OR=1.78), levels were seen in cases. Regression analysis showed that anti-β2GPI IgM (OR=8.90; 95% CI=1.23–64.63) was associated with early RSA, while anti-annexin V IgG (OR=9.35, 95% CI=1.44–60.86) was associated with late RSA. For combined early + late RSA, the only variable selected was BMI (OR=0.93; 95% CI=0.87–0.99), and neither anti-annexin V nor anti-β2GPI IgM and IgG were associated with early + late RSA. Anti-annexin V and anti-β2GPI appear to be independent risk markers of RSA.