Hypercoagulation | Causes & Risk Factors


What causes hypercoagulation?

Certain proteins in your blood are supposed to keep your blood from clotting too much. Some people do not have enough of these proteins. In other people, these proteins are not doing their job properly, or there may be extra proteins in the blood that causes too much clotting.

Some people are born with a tendency to develop clots. This tendency is inherited (which means it runs in your family).

Certain situations or risk factors can make it more likely for your blood to clot too much. These situations include the following:

  • Sitting on an airplane or in a car for a long time
  • Prolonged bed rest (several days or weeks at a time), such as after surgery or during a long hospital stay
  • Surgery (which can slow blood flow)
  • Cancer (some types of cancer increase the proteins that clot your blood)
  • Pregnancy (which increases the pressure in your pelvis and legs and can cause blood clots to form)
  • Using birth control pills or receiving hormone replacement therapy (which can slow blood flow)
  • Smoking

What are some of the risk factors of hypercoagulation?

You may be at risk of hypercoagulation if any of the following are true:

  • You have relatives with abnormal or excessive clotting
  • You had an abnormal clot at a young age
  • You got clots when you were pregnant, were using birth control pills or were being treated with hormone replacement therapy
  • You have had several unexplained miscarriages

Written by familydoctor.org editorial staff

Reviewed/Updated: 03/14
Created: 09/00