You are evaluating a 25-year-old gravida 5 para 1 at 6 weeks estimated gestation. She has a history of three consecutive spontaneous miscarriages. Her workup has been negative except for a positive lupus anticoagulant on two occasions, separated by 6 weeks. You make the diagnosis of antiphospholipid antibody syndrome. She has no previous history of venous or arterial thrombosis. The best medical management at this time is:
a) Low-dose aspirin
b) Low-molecular-weight heparin (LMWH)
c) Warfarin
d) Corticosteroids