Risk factors that promote DVT include: history of thrombotic event, thrombophilia (antithrombin deficiencies, antiphospholipid antibodies, Leiden factor V, methylenetetrahydrofolate reductase (MTHFR), etc.), use of contraceptives, and prolonged immobilization. Here, MTHFR is linked to hyperinsulinemic hypoglycemia, familial, 4.