Antiphospholipid antibodies and pregnancy outcomes in women heterozygous for Factor V Leiden

Antiphospholipid antibodies are associated with a spectrum of pregnancy complications, including preeclampsia and small for gestational age (SGA) fetuses. We sought to assess anticardiolipin and anti-β2-glycoprotein I (anti-β2-GPI) IgG and IgM antibody prevalence and the relationship of these antibodies to pregnancy complications in women with the Factor V Leiden (FVL) mutation. The study comprised a secondary analysis of a multicenter, prospective observational study of FVL prevalence among 5188 asymptomatic pregnant women. A subset of 362 women (117 FVL heterozygotes, 245 matched controls) had serum collected at the time of the original study and underwent serum analysis for anticardiolipin and anti-β2-GPI IgG and IgM as a part of this analysis. The primary outcome was preeclampsia and/or SGA (<10%). The overall prevalence of anticardiolipin and anti-β2-GPI IgG and IgM antibodies was low and did not vary with FVL status. Forty-seven women (13.0%) developed preeclampsia and/or SGA. There were no differences in primary outcome rates between women with and without aPL antibodies, regardless of FVL mutation status. Among FVL carriers, the presence of antiphospholipid antibodies does not appear to contribute to adverse pregnancy outcome.