Venous thromboembolic disease is a common pathology in the general population (1.5/1000), the prognosis of which depends in particular on the risk of recurrence. This risk depends essentially on whether the thrombotic episode was provoked or not. Thus, patients who present a thromboembolic event without any contributing factor have a high risk of recurrence, which encourages clinicians to continue anticoagulant treatment for a long time. However, anticoagulant treatment is the leading cause of hospitalization for iatrogenic causes and the leading cause of iatrogenic mortality. The benefit-risk balance of treatment must be evaluated regularly, which requires a good knowledge of the risk factors for thrombotic recurrence and the risk factors for hemorrhage.