Bleeding complications and antithrombotic treatment in 264 pregnancies in antiphospholipid syndrome

PurposeThe purpose of this study was to evaluate the safety of antithrombotic treatments prescribed during pregnancy in patients with antiphospholipid syndrome (APS).MethodsThis international, multicenter study included two cohorts of patients: a retrospective French cohort and a prospective US cohort (PROMISSE study). Inclusion criteria were (1) APS (Sydney criteria), (2) live pregnancy at 12 weeks of gestation (WG) with (3) follow-up data until six weeks post-partum. According to APS standard of care, patients were treated with aspirin and/or low-molecular weight heparin (LMWH) at prophylactic (pure obstetric APS) or therapeutic doses (history of thrombosis). Major bleeding was defined as abnormal blood loss during the pregnancy and/or post-partum period requiring intervention for hemostasis or transfusion, or during the peripartum period greater than 500 mL and/or requiring surgery or transfusion. Other bleeding events were classified as minor.ResultsTwo hundred and sixty-four pregnancies (87 prospecti...