9 Risk Factors Of Blood Clots: Clues You Might Miss

Though it could be considered the third highest cause of death behind heart disease and cancer, most people live their lives unaware of the threat posed by blood clots. If you are one of these people, protect yourself by reviewing these common risk factors that contribute to the development of blood clots.

Being Overweight or Obese

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The veins in those who are obese are weakened and more likely to swell from the pressure placed on the legs and feet. This could cause circulation problems that increase the likelihood of developing blood clots.

Hormone or Birth Control Pills

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The principle hormone in birth control pills and hormone therapy is estrogen. Estrogen increases the chances of clots occurring in the blood. According to Harvard Health Publications, testosterone therapy has similar risk factors for increasing blood clots in men.

Family History of Blood Clots

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Genetics and family history play a significant role in the chances of developing blood clots. According to Advanced Vein Care, disorders related to blood clots, such as anti-thrombin deficiency, Protein C or Protein S deficiency, and Factor V Leiden, are often inherited.

Bed Rest

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Being confined to bed rest decreases the contraction of leg muscles, which disrupts the circulation of blood. When blood does not circulate, blood clots are likely to develop.


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Regular travel is a risk factor for developing blood clots. The immobility of sitting in place for extended periods limits the muscle contractions needed for proper circulation.

Having Surgery

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Veins are often cut as part of surgery, and during the healing process, the risk of blood clots forming is increased. Knee and hip replacement surgeries are even riskier, as tissue is often released into the blood, which can cause clotting.

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Smoking not only impedes proper blood circulation in the body, it also increases the blood’s tendency to form clots.

Being Pregnant or Having Just Had a Baby

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The added weight that is placed on the legs and feet during pregnancy carries the same risks as being overweight or obese. The pressure increases the chances of blood clots.

Being a Cancer Survivor

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Forms of cancer, such as those affecting the lungs, ovaries and pancreas, cause substances to be released that encourage blood clotting in the body. Common cancer treatments such as chemotherapy can also contribute to the conditions that cause blood clots.

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