Antiphospholipid syndrome characteristics and adverse pregnancy outcomes after 20 weeks of pregnancy

Objective: To assess outcomes after 20 weeks of pregnancy according to autoantibody profile and clinical presentation of maternal antiphospholipid syndrome (APS). Methods: The present retrospective cohort analysis included women diagnosed with APS at a tertiary medical center in Israel between January 1, 2012, and December 31, 2016. Anticardiolipin antibodies, anti-β2-glycoprotein antibodies, and lupus anticoagulant were assessed. Participants were stratified by type of APS (obstetric vs thrombotic), antibody profile, and antibody titer (low vs high). Primary composite outcomes were rated as severe (stillbirth, fetal growth restriction at <34 weeks, severe pre-eclampsia, or delivery at <32 weeks) and mild (stillbirth, any fetal growth restriction, any pre-eclampsia, or delivery at <34 weeks). Results: A total of 99 women were included in the analysis. The primary composite outcomes were similar regardless of stratification. Lupus anticoagulant positivity was associated with delivery before 37 weeks. When compared with low antibody titer, high antibody titer was associated delivery at or before 32 weeks (P=0.045) and 34 weeks (P=0.029). Conclusion: High antibody titer might be associated with an increased risk of severe prematurity among pregnant women with APS.