Those subclinical lesions that are caused by low-risk types of HPV usually clear spontaneously within one year.
As for subclinical lesions caused by high-risk types of HPV:
- 70% are suppressed within one year by the immune system
- 90% are suppressed within 3 years by the immune system
- In 10% of the cases, the immune system cannot suppress the infection caused by an oncogenic type of HPV. The infection persists or is temporarily suppressed and recurs later. In these cases there is an increased risk for mutations and appearance of premalignant (precancerous) lesions initially and then cancer.