F5 and thrombophilia: Hereditary thrombophilia includes deficiencies of anti-thrombin III, protein C and S, and mutation in factor V Leiden genes.10 Although the last one is responsible for more than 50% of cases, it is associated with mild thrombophilia.10,14 Moreover, mutations in prothrombin gene is associated with lower risk, protein C and S deficiencies with moderate risk and anti-thrombin III deficiencies with higher risk of thromboembolic events.14