Effectiveness of varying number of doses and timing between doses of quadrivalent HPV vaccine against severe cervical lesions

Women vaccinated with 3 doses of qHPV showed a reduced risk of CIN2+ if they were vaccinated before age 20, with a further reduced risk if vaccinated before age 17. Vaccination with 2 doses, with the second dose 5 months or longer after the first dose, did not yield an increased risk of CIN2+, compared to 3 doses.