Deep Vein Thrombosis - What Increases Your Risk

What Increases Your Risk

Many factors increase your risk for deep vein thrombosis. Some risk factors do not change, such as genetic blood irregularities, while other risk factors may change according to circumstances, such as pregnancy.

Major risk factors

Major risk factors for deep vein thrombosis include:

• Prolonged bed rest (more than 3 days), such as during a hospital stay.
• Abnormal blood clotting (hypercoagulable state), usually a result of inherited genes from one or both parents.
• Injury.
• Surgery, particularly major hip or knee surgery, neurosurgery, and abdominal or chest surgery associated with cancer.
• Cancer and its treatment.
• Paralysis from a spinal cord injury.
• Having a central venous catheter during a hospital stay.

Minor risk factors

Most of these risk factors are minimal by themselves but may become more significant in combination. Research continues on the importance of these risk factors and how they interrelate.

Your risk for deep vein thrombosis may be increased by:

• Certain health conditions such as varicose veins, heart attack, heart failure, and stroke.
• A long airplane flight or car trip.
• Pregnancy, especially immediately after giving birth or after a cesarean section.
• Increasing age. People older than 40 have a greater risk of developing deep vein thrombosis.
• Being overweight.
• Taking birth control hormones, such as daily pills or weekly patches. Current evidence shows that a woman's risk of developing pulmonary embolism, a complication of deep vein thrombosis, increases while she is taking birth control hormones. Past use of birth control pills does not appear to increase this risk.
• Current use of hormone therapy (hormone replacement therapy or estrogen replacement therapy), raloxifene (Evista) for osteoporosis, or the breast cancer treatment tamoxifen (Nolvadex).
• Smoking.