When should I consider referring a patient with Factor V Leiden for specialist hematology assessment?

Guideline-aligned answer with reasoning, red flags and references. Clinically reviewed by Dr Kola Tytler MBBS CertHE MBA MRCGP.

Posted: 17 August 2025Updated: 17 August 2025 Guideline-Aligned (High Confidence) Clinically Reviewed
Dr Kola Tytler MBBS CertHE MBA MRCGPClinical Lead • iatroX

Consider referring a patient with Factor V Leiden mutation for specialist hematology assessment if they have had an unprovoked venous thromboembolism (VTE), especially deep vein thrombosis (DVT) or pulmonary embolism (PE), and there is a first-degree family history of VTE. This is because thrombophilia testing, including for Factor V Leiden, is clinically useful in such cases to guide the duration and intensity of anticoagulation treatment and to assess recurrence risk.

Referral is also recommended for women with Factor V Leiden mutation who are planning pregnancy or are pregnant, particularly if they have a history of VTE or an abnormal thrombophilia screen, to enable specialist pre-conception counselling and management planning.

Testing and referral are generally not indicated for patients with provoked VTE or those continuing anticoagulation treatment where management would not change.

Educational content only. Always verify information and use clinical judgement.