Being aware of risk factors, and especially of your own risk factors is really important in helping you to avoid and protect yourself from thrombosis.

The the most common risk factors for thrombosis are:

  • Hospitalization for illness or surgery
  • Major surgery, particularly of the pelvis, abdomen, hip, knee
  • Severe trauma, such as a car accident
  • Injury to a vein that may have been caused by a broken bone or severe muscle injury
  • Hip or knee replacement surgery

  • Cancer and cancer treatments
  • Contraceptive pill for birth control in particular those that contain estrogen, such as the pill, patch or ring
  • Pregnancy, (including the six weeks after the baby is born)
  • Hormone therapy (HRT), which contains estrogen

  • A family history of blood clots
  • Obesity
  • Long-term bed rest
  • Long periods of inactivity including sitting for long period of time, especially with legs crossed

It is important that you discuss this with your doctor if any of these risk factors apply to you.

Find out more about your risk of blood clots in hospital

This film has been developed by Kings Thrombosis Centre and Thrombosis UK and is available free of charge to download and share with friends, family, work colleagues and in hospitals and medical settings.





Most blood clots occur as a result of hospitalisation. This can be because you may undergo surgery, be receiving treatment that might increase the risk of blood clots or also because you can be very immobile when in hospital and for a period of time after discharge.

  • Surgery and some medical treatments can increase your risk of developing DVT

If you're thought to be at risk of developing DVT, talk with your healthcare team about measures to prevent a blood clot forming.

  • Make sure you have enough to drink so you don't become dehydrated
  • Compression devices may be offered that are inflatable and inflate at regular intervals to squeeze your legs and encourage blood flow.
  • If possible, move about and take regular walks. Keeping mobile can help prevent blood clots.

You can reduce the risk of developing a DVT by making changes to your lifestyle, such as:

  • Not smoking
  • Eating a healthy, balanced diet
  • Taking regular exercise
  • Maintaining a healthy weight

If you're planning a long-distance plane, train or car journey, make sure you:

  • Drink plenty of water
  • Avoid drinking excessive amounts of alcohol because it can cause dehydration
  • Avoid taking sleeping pills because they can cause immobility
  • Try to do simple leg exercise such as regularly flexing your ankles
  • When possible, move about and take short walks

Find out more

Download the free Let’s Talk Clots patient information app.

Scan the QR Code to find the app in the App Store

Scan the QR Code to find the app in the Google Play Store