- Mutated genes (such as factor V Leiden, factor II).
- Decreased amounts of certain proteins. These may include protein C, protein S, and antithrombin III.
- Increased levels of other substances. These may include antiphospholipid antibodies and lupus anticoagulant.
Other people get blood clots because of a health problem. Blood clots can happen after surgery or injury. And they can happen when a person doesn't move around for a long time.
There are several tests that can help find the cause of a blood clotting problem. Talk to your doctor about whether you need testing.
These tests may include:
- Protein C.
- Protein S.
- Factor V Leiden.
- Antiphospholipid antibody
- Lupus anticoagulant.