Symptoms of thrombophilia
Most people do not realise they have thrombophilia until it causes a blood clot.
Symptoms of a blood clot can include:
- throbbing pain and swelling in your legs and arms (deep vein thrombosis)
- sudden breathing difficulties, chest pain and coughing up blood (pulmonary embolism)
Having repeated miscarriages can also be a symptom of thrombophilia.
Urgent advice: Ask for an urgent GP appointment or get help from NHS 111 if you:
- have throbbing or cramping pain in 1 leg, usually in the calf or thigh
- get swelling in 1 leg
- have red, darkened or warm skin on your leg
- suddenly have difficulty breathing
- are coughing up blood
These could be the symptoms of a blood clot in your leg or your lungs.
You may get pain and swelling in your arm or tummy instead if that's where the blood clot is.
You can call 111 or get help from 111 online.
Immediate action required: Call 999 or go to A&E if:
- you have severe difficulty breathing
- you feel pain in your chest or upper back
- your heart is beating very fast
- someone has passed out
These could be signs of a pulmonary embolism or another serious condition.
Do not drive yourself to A&E.
The person you speak to at 999 will give you advice about what to do.
Types of thrombophilia
There are 2 types of thrombophilia, which have different causes.
| Type | Why it happens |
|---|---|
|
Inherited thrombophilia |
You’re born with certain altered genes that increase your risks of blood clots |
|
Acquired thrombophilia |
You get an increased risk of clots in later life due to another condition, such as antiphospholipid syndrome or a problem with your liver or kidneys |
If you have inherited thrombophilia, there is a chance you could pass the condition to any children you have. Your doctor can tell you more.
Diagnosing thrombophilia
You may be offered a blood test for thrombophilia if:
- you had a blood clot and it’s not obvious why you had it (for example, you’re not overweight and do not smoke)
- a close family member (parent, brother or sister) has inherited thrombophilia
- you’ve had 3 or more miscarriages
Blood tests can check for altered genes or changes in your blood cells linked to thrombophilia.
You may be offered ultrasound scans or CT scans to see if there are any problems with your blood vessels.
Treatment for thrombophilia
There is currently no cure for thrombophilia that’s caused by altered genes you inherit from your parents (inherited thrombophilia).
Thrombophilia that starts later in life (acquired thrombophilia) can sometimes get better if the underlying cause is treated.
If your doctor thinks your overall risk of a blood clot is low, you may not need any treatment.
If you need treatment, you’ll usually be offered anticoagulant medicine. It works by making your blood less sticky so it’s less likely to clot.
Things you can do if you have thrombophilia
For many people, thrombophilia does not have a big impact on their life. But there are things you can do to reduce the risk of getting blood clots.
Do
-
stay active
-
try to lose weight if you're overweight
-
drink plenty of water to avoid dehydration – you're more likely to get a clot if you're dehydrated
-
wear flight stockings or flight socks to improve your blood flow on long flights – a pharmacist can advise you about this
Don’t
-
do not smoke
-
do not drink lots of alcohol – this can make you dehydrated
-
do not sit for long periods without moving, if you can avoid it
Important
Tell your doctor or healthcare professional that you have thrombophilia before having any medical procedures or starting any new prescription medicines (including contraception).
Some medicines may not be safe for you, and you may need extra treatment or monitoring when you have medical procedures.
Thrombophilia and pregnancy
If you are pregnant or planning a pregnancy, you should contact your GP if you have thrombophilia.
You may need additional treatment and monitoring to reduce complications.
Page last reviewed: 08 January 2025
Next review due: 08 January 2028