Antiphospholipid antibodies may be detected by solid phase anticardiolipin antibody tests, the lupus anticoagulant test, or standard tests for syphilis (STS). The occurrence of these antibodies has been associated with venous or arterial thrombosis, fetal loss, and possibly thrombocytopenia. Other suggested features that may be associated with these antibodies include livedo reticularis, migraine, chorea, and heart valve lesions. Uncontrolled studies of small numbers of affected women with recurrent fetal loss suggest that prednisone and aspirin therapy during pregnancy may improve pregnancy outcome. Anticoagulant therapy is recommended for patients with thrombosis for as long as antiphospholipid antibodies persist.