Each year as many as 600,000 Americans (half of them women) will suffer deep vein thrombosis (DVT) and the potentially deadly complication pulmonary embolism.1 In 9 out of 10 cases a DVT can be prevented by getting your DVT risk factors under control and taking steps to prevent a clot from forming in situations that can trigger them.2
Step 1: Identify and Control Your DVT Risk Factors
The first step towards preventing DVT is to know if you have conditions or characteristics that increase your risk of developing blood clots, called risk factors. See Am I at Risk for DVT for a list of common DVT risk factors and links to articles that tell you what they are, how to know if you have them, and how they affect your risk of blood clots in the veins.
If you have any of the risk factors for DVT, you can lower your risk by working with your doctor to get them under control. Some basic steps you can take to prevent a DVT:
- If you smoke, get the help you need to quit smoking
- Eat a heart-healthy diet that includes plenty of fruit, green vegetables, fish, and whole grains; cut down on red meat, processed foods, saturated fat, and cholesterol
- Maintain a healthy weight. If you are overweight or obese, work with your doctor to decide on a weight loss plan and set reasonable goals. Losing even 10% of your body weight can make a huge difference.
- Get regular exercise – at least 30 minutes a day 5 or more days a week; the more active you are, the better
- If you have diabetes, control your blood sugar levels and practice proper foot care: check your feet every day for cuts, blisters, red marks, or swelling
- If you have other heart conditions, stick to your treatment plan and take all your medications as prescribed
- If you are taking birth control pills that contain estrogen, talk to your doctor about alternatives, especially if you smoke or have other DVT risk factors.
- Discuss with your doctor the risks and benefits of hormone replacement therapy (HRT) for menopausal symptoms, which raises the risk of DVT. If you decide HRT is right for you, take it for the shortest time possible.
- If you have varicose veins or other signs of vein disease, talk to your doctor about treatment to prevent blood clots
- If your doctor has prescribed medication to prevent clots:
- Always take them as prescribed and refill your prescription before it runs out
- Know what side effects to watch for and talk to your doctor if you experience them—a different dose or a different drug may be able to reduce or eliminate side effects
- Watch how much vitamin K you are eating; it can interfere with some blood- thinning drugs. Green leafy vegetables and canola and soybean oils have high levels of vitamin K
- Ask your doctor if compression stockings can help you prevent blood clots if you are at high risk for DVT. These prescription stockings squeeze the veins in your legs, helping to move blood back towards the heart.
- Have regular check-ups with your doctor and discuss how your prevention plan is going. Click here for more on screening tests for women and who should get them.
Step 2: Know How to Avoid Triggering a DVT
Certain high-risk situations can sometimes "trigger" a blood clot to form, especially in women with DVT risk factors. If you are at risk for blood clots in the veins and you are going to be exposed to these situations, there are steps you can take to reduce your risk.
Sitting still for a long time while traveling, whether on an airplane flight or in a car, bus, or train, increases your risk of DVT. Immobility during travel of 4 hours or more doubles your risk of DVT for weeks after, and longer travel increases it even more.3,4
Some tips to prevent blood clots while traveling or sitting for long periods:
- Get up and walk around once every hour or so
- Do some simple leg exercises every 20 minutes while sitting:
- Raise and lower your heels while keeping your toes on the floor
- Raise and lower your toes while keeping your heels on the floor
- Lift your feet off the floor and draw circles with your toes. Continue for 15 seconds and then reverse direction.
- Raise one leg off the floor and straighten it. Hold for a moment and then bring it back down. Repeat with the other leg.
- Keeping your foot on the floor, slide it forward until your leg is straight. Repeat with the other leg.
- Tighten and release your leg muscles.
- Drink plenty of water, and avoid alcohol and caffeine
- Wear loose, comfortable clothing
- If you are at high risk for DVT, ask your doctor if you should wear compression stockings or take blood-thinning medications before a long trip
Long periods of immobility during hospitalization or after major surgery are common blood clot triggers. Surgery itself can also injure blood vessel and make blood more likely to clot. Studies have found that only one in three patients receives proven DVT-prevention measures in the hospital, and women may be less likely to receive them than men.2,5
You are at highest risk for DVT during hospitalization or surgery if you have other DVT risk factors and:
- You are going to be confined to a bed or wheelchair for 3 or more days
- You are going to be hospitalized for a week or more
- You are having surgery for a leg injury such as a pelvis, hip, or leg fracture
- You are having major cardiac or thoracic (chest) surgery or are undergoing a hip or knee replacement
Because healthcare providers often overlook proven DVT prevention strategies, women at risk need to be proactive to ensure they receive the best possible care. Some tips to help lower your risk of blood clots:
- Talk to your doctors or nurses about your blood clot history and ask them what can be done to lower your risk
- If you are having elective surgery, ask your doctor if you should stop taking estrogen-containing birth control pills 4 weeks before the surgery
- Drink plenty of water; dehydration thickens the blood and increases your risk of clots
- Take any prescribed medications as directed
- Ask your healthcare team about leg stretches and exercises you can do in bed to get your muscles working
- Get up and moving as soon as possible after an injury, illness, or surgery. The sooner you are active, the lower your risk of clots
- Ask your doctor about graduated compression stockings to reduce the risk of clots
If you need extended bed rest, another device that can be used to prevent blood clots is called an intermittent pneumatic compression device (IPC). An air pump machine alternately inflates and deflates knee-high boots to force blood out of the legs and back to the heart.
Because of hormonal and other changes, women are at increased risk for DVT during pregnancy and the first few months after the baby is born (called the postpartum period). A woman is at higher risk if she has other DVT risk factors. Depending on your risk, you may need to take blood-thinning medications or wear compression stockings during and after pregnancy to prevent clots.
To learn more, see Pregnancy & Vein Disease Risk.
Step 3: Know how to Recognize the Signs and Symptoms of DVT
Working with your doctor to identify conditions that are putting you at risk and getting them under control will go a long way towards preventing a DVT. Unfortunately, it is not possible to eliminate the risk of DVT completely. Be sure you know how to recognize the signs of DVT and seek prompt medical attention if you experience them. Proven treatments are available to prevent future blood clots, avoid a potentially deadly pulmonary embolism, and prevent vein damage that can cause long-term vein disease.
- U.S. Department of Health and Human Services. The Surgeon General's Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism. Washington, DC: U.S. Department of Health and Human Services; September 15 2008.
- Goldhaber SZ, Tapson VF. A prospective registry of 5,451 patients with ultrasound-confirmed deep vein thrombosis. Am J Cardiol. Jan 15 2004;93(2):259-262.
- Cannegieter SC, Doggen CJ, van Houwelingen HC, Rosendaal FR. Travel-related venous thrombosis: results from a large population-based case control study (MEGA study). PLoS Med. Aug 2006;3(8):e307.
- Kuipers S, Schreijer AJ, Cannegieter SC, Buller HR, Rosendaal FR, Middeldorp S. Travel and venous thrombosis: a systematic review. J Intern Med. Dec 2007;262(6):615-634.
- Anderson FA, Jr., Wheeler HB, Goldberg RJ, Hosmer DW, Forcier A, Patwardhan NA. Physician practices in the prevention of venous thromboembolism. Ann Intern Med. Oct 15 1991;115(8):591-595.