This guideline updates and widens the scope of the previous British Society for Haematology (BSH) Clinical guidelines for testing for heritable thrombophilia1 to include both heritable and acquired thrombophilia.

The term thrombophilia is generally used to describe hereditary and/or acquired conditions associated with an increased predisposition to thrombosis. Heritable thrombophilia refers to genetic disorders of specific haemostatic proteins. These guidelines focus only on the factors that are identified from laboratory testing and therefore exclude disorders such as cancer, inflammatory conditions and obesity that are associated with thrombosis through multiple mechanisms.