Risk factors for developing<unk>  include: * Genetic Markers: HLA-DR4, HLA-DR7, and HLA-DRw53 * Race: Blacks, Hispanics, Asians, and Native Americans
Antiphospholipid syndrome
Protein C deficiency
Protein S deficiency
Catastrophic antiphospholipid syndrome
Acquired haemophilia
Antithrombin III deficiency
Sticky platelet syndrome
Congenital hypofibrinogenemia