| Provoking factor | Risk of recurrence, % | |
|---|---|---|
| Within 1 yr of stopping therapy | Within 5 yr of stopping therapy | |
| Recent surgery | 1 | 3 |
| Nonsurgical trigger (estrogen, pregnancy, leg injury, flight length > 8 h) | 5 | 15 |
| Unprovoked venous thromboembolism | 10 | 30 |
| Cancer | 15 | – |