Lupus anticoagulant is an autoimmune disorder caused by antibodies that bind to phospholipids and proteins associated with the cell membrane. This antibody has the peculiar nature of causing a delay in coagulation in laboratory tests (the partial thromboplastin time) while clinically predisposing for thrombosis. It is also known as lupus antibody, LA and lupus inhibitor. Together with anticardiolipin antibodies, LA causes the bulk of antiphospholipid syndrome.