Recurrent miscarriage, antiphospholipid antibodies and the risk of thromboembolic disease

Miscarriage affects 15 % of women, and while most are sporadic, there is a subset comprising 2-5 % of couples that suffers recurrent miscarriage (RM). Much work has been carried out to try to identify the RM underlying mechanisms. A subgroup of women with RM has been demonstrated to be in a prothrombotic state before pregnancy. The long-term health implications of this hypercoagulability may imply an increased risk of thrombotic events, including ischemic heart disease. Moreover, the presence of antiphospholipid antibodies (aPL), rather than thrombophilic genetic defects (i.e., factor V Leiden or prothrombin G202010A mutation) in patients with RM, is a determinant of thrombotic events later in life, especially among those patients having also classic cardiovascular risk factors. These facts may have therapeutic implications. The efficacy of long-term thromboprophylaxis and its associated risk of bleeding is a complex problem in aPL-positive patients who have not developed previous thrombosis or in patients with antiphospholipid syndrome with isolated obstetric morbidity (i.e., RM). While most authors advocate the use of antithrombotic therapy only in patients with aPL and thromboembolic events, there is no consensus as to whether patients who have not experienced yet any thrombotic event might also be given prophylaxis. Low-dose aspirin may be effective in the prevention of thrombosis for asymptomatic, persistently aPL-positive individuals who have additional thrombosis risk factors, i.e., hypertension and lupus anticoagulant have been found to be independent risk factors for thrombosis in aPL carriers, and therefore, the use of thromboprophylaxis in these high-risk subjects could be recommend.