Participants were followed to a maximum age of 38 years, while those vaccinated before the age of 17 were followed to a maximum age of 34.² The researchers utilized Poisson regression to estimate incidence rate ratios of invasive cervical cancer among vaccinated versus unvaccinated women, adjusting for a range of potentially influential factors.¹ These included age, calendar time, county of residence, mother’s country of birth, parental education, parental income, and medical histories such as high-grade cervical lesions and non-cervical cancers.1,2
During the follow-up, 365,502 participants, or 39.5% of the total cohort, received at least 1 dose of the quadrivalent HPV vaccine. A total of 930 cases of invasive cervical cancer were identified, consisting of 97 cases in vaccinated individuals and 833 cases in unvaccinated individuals. Among participants vaccinated before 17 years, the overall fully adjusted incidence rate ratio was 0.21 (95% confidence interval (CI) 0.13 to 0.32).¹ This represented a 79% lower risk of cervical cancer compared with the unvaccinated group.² Within this younger group, sustained protection was observed 13-15 years after vaccination, with an incidence rate ratio of 0.23 (95% CI 0.11 to 0.46), reflecting a 77% lower risk.1,2
For individuals who received the vaccine at 17 years or older, the overall fully adjusted incidence rate ratio was 0.63 (95% CI 0.49 to 0.81), representing a 37% lower risk compared with the unvaccinated group. Significant incidence reductions in this group were observed during years 10-12 (incidence rate ratio 0.54, 95% CI 0.33 to 0.86) and years 13-15 (incidence rate ratio 0.23, 95% CI 0.08 to 0.60) after vaccination.¹ The risk reduction at 13-15 years for the older group was 77%.²
At the population level, the results showed a decline in cervical cancer cases over time.² The school-based cohort had a 72% lower risk of cervical cancer after adjustment for covariates compared with the opportunistic cohort (incidence rate ratio 0.28, 95% CI 0.09 to 0.89).¹
The rate of invasive cervical cancer was highest in women born between 1985 and 1988, reaching approximately 250 cases per 100,000 by age 38.² This rate progressively decreased for women born in 1989-1992 and 1993-1998, and was significantly lower for women born between 1999 and 2001, at 4 per 100,000 by age 24.²
The authors noted that these are observational findings and acknowledged certain limitations, such as the possibility that some vaccinated women were misclassified as unvaccinated.² They also could not rule out a healthy volunteer bias or the influence of unmeasured factors such as smoking and sexual activity. However, the researchers concluded that the significantly reduced risk of invasive cervical cancer following quadrivalent HPV vaccination persisted throughout long-term follow-up.
“This study provides evidence of sustained protection against invasive cervical cancer throughout 18 years of follow-up, with no indication of waning protection,” the authors stated. “These findings further support global strategies for eliminating cervical cancer as a public health problem by achieving high-coverage of routine HPV vaccination.
References:
- Wu S, Deng Y, Lepp T, et al. Extended follow-up of invasive cervical cancer risk after quadrivalent HPV vaccination: nationwide, register based study. BMJ. 2026;392:e087326. doi:doi.org/10.1136/bmj-2025-087326
- HPV vaccination provides “sustained protection” against cervical cancer. BMJ Group. Press release. Published February 25, 2026. Accessed February 27, 2026. http://eurekalert.org/news-releases/1117622?-