Many factors can increase your risk of developing deep vein thrombosis (DVT), and the more you have, the greater your risk. Risk factors for DVT include:

  • Inheriting a blood-clotting disorder. Some people inherit a disorder that makes their blood clot more easily. This inherited condition may not cause problems unless combined with one or more other risk factors.
  • Prolonged bed rest, such as during a long hospital stay, or paralysis. When your legs remain still for long periods, your calf muscles don't contract to help blood circulate, which can increase the risk of blood clots.
  • Injury or surgery. Injury to your veins or surgery can increase the risk of blood clots.
  • Pregnancy. Pregnancy increases the pressure in the veins in your pelvis and legs. Women with an inherited clotting disorder are especially at risk. The risk of blood clots from pregnancy can continue for up to six weeks after you have your baby.
  • Birth control pills or hormone replacement therapy. Birth control pills (oral contraceptives) and hormone replacement therapy both can increase your blood's ability to clot.
  • Being overweight or obese. Being overweight increases the pressure in the veins in your pelvis and legs.
  • Smoking. Smoking affects blood clotting and circulation, which can increase your risk of DVT.
  • Cancer. Some forms of cancer increase the amount of substances in your blood that cause your blood to clot. Some forms of cancer treatment also increase the risk of blood clots.
  • Heart failure. People with heart failure have a greater risk of DVT and pulmonary embolism. Because people with heart failure already have limited heart and lung function, the symptoms caused by even a small pulmonary embolism are more noticeable.
  • Inflammatory bowel disease. Bowel diseases, such as Crohn's disease or ulcerative colitis, increase the risk of DVT.
  • A personal or family history of deep vein thrombosis or pulmonary embolism (PE). If you or someone in your family has had DVT or PE before, you're more likely to develop DVT.
  • Age. Being over age 60 increases your risk of DVT, though it can occur at any age.
  • Sitting for long periods of time, such as when driving or flying. When your legs remain still for many hours, your calf muscles don't contract, which normally helps blood circulate. Blood clots can form in the calves of your legs if your calf muscles aren't moving for long periods.
Jul. 03, 2014

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