Indicator Explainer
Factor V Leiden
An abnormality that refers to mutation of factor V Leiden, which is a variant of human factor V. It results in thrombophilia, deep vein thrombosis, and a slightly increased risk of miscarriage.
This page explains what the indicator is and how results are interpreted in general terms. Reference ranges depend on the laboratory, the method, and your own situation — no single “normal value” applies to everyone. This page is health information, not a diagnosis. For symptoms, treatment, or urgent concerns, contact a healthcare professional.
When it is tested
Source: National Cancer Institute, NCI Thesaurus 26.09d, C98573. NCI definition, reproduced without modification under CC BY 4.0. Source identity and definition checked automatically on 2026-10-20. No individual clinical interpretation or human reviewer is asserted.
Reading results
Reference intervals and interpretation depend on the laboratory, specimen, method and clinical context. This source definition is educational information; it does not establish a diagnosis, product approval or suitability for an individual.
Also Known As
References
- NCI Thesaurus 26.09d — Factor V Leiden (C98573)
- Source: National Cancer Institute, NCI Thesaurus 26.09d, C98573. NCI definition, reproduced without modification under CC BY 4.0.
- Reply to "Important Methodological and Statistical Concerns Regarding the Association of Factor V Leiden and MTHFR Polymorphisms With COVID-19 Outcomes". — Immun Inflamm Dis, 2026-10-01 (PMID 42853025; literature)
- Association between routine anticoagulation and pregnancy outcomes in women with heterozygous Factor V Leiden genotype. — Mol Biol Rep, 2026-09-21 (PMID 42766054; literature)
- Clotting Beyond Boundaries: Extensive Iliocaval Thrombosis Revealing Homozygous Factor V Leiden Mutation in a Young Adult Following Prolonged Air Travel. — Cureus, 2026-09-18 (PMID 42761862; literature)
- Obese Adolescent with Factor V Leiden-Related Pulmonary Embolism: Case-Based Insight into Paediatric Thrombosis Management. — Diagnostics (Basel), 2026-09-03 (PMID 42739272; literature)
- Important Methodological and Statistical Concerns Regarding the Association of Factor V Leiden and MTHFR Polymorphisms With COVID-19 Outcomes. — Immun Inflamm Dis, 2026-09-01 (PMID 42712146; literature)