Your circulatory system, which propels blood throughout your body, is a work of art.

But sometimes it can go awry and causeblood clots, which can be life-threatening.

Blood clots dont always cause symptoms, but when they do, theyre likely to affect your legs.

PreventingBloodClots

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A model known asVirchows triadbreaks down the three main causes behind blood clots.

Various risk factors can contribute to these blood-clot causes.

Some are non-modifiable risk factors, meaning you unfortunately cant control them.

Below, youll find the most common risk factors for developing a blood clot.

And the risk doesnt go away as soon as a person gives birth.

Seven to 12 weeks postpartum, that number was down to three cases out of every 100,000 deliveries.

After that, the risk of a blood clot went back to what it was pre-pregnancy.

Combined hormonalbirth controluses estrogen and progestin to help prevent an unintendedpregnancy.

Thats typically a great thing, but estrogen in particular raises a persons risk of DVT.

Otherwise, your overall risk of developing a blood clot onbirth control pillsis low.

The longer youre still, the greater your risk of developing a clot, Dr. Fischer says.

Lighting up damages a whole host of your bodys processes, and your circulatory system is no exception.

But quitting smoking is usually easier said than done.

Its definitely worth quitting smoking for your overall health, Dr. Evans says.

The reasons for this arent well understood, Dr. Evans says.

Still, theres a lot of uncertainty around this one.

Even healthy elderly patients are at higher risk of clots than their younger counterparts, Dr. Evans says.

There is something about the biology of aging that increases clotting potential.

Lying in bed after an operation also increases your risk since youre not moving as much.

National Library of Health.

Others, like Factor V Leiden, fall on the opposite side of the spectrum.

These canmake your blood hypercoagulable, meaning it clots way too easily.

It sounds strange, but inflammatory bowel diseases likeCrohns diseaseorulcerative colitisraise your risk of getting a blood clot.

Cancer also increases a persons risk of having blood clots.

In general,the bodys clotting system gets exaggeratedin people who have cancer, Dr. Evans says.

Specifically, various types of cancer may increase proteins that cause clotting, according to theAmerican Heart Association.

Having a detailed conversation with your doctor about your concerns is a great step.

And if you suspect you have DVT or a pulmonary embolism, go to your localemergency roomimmediately.