WEDNESDAY, March 4, 2026 (HealthDay News) -- Following quadrivalent human papillomavirus (HPV) vaccination, the risk for invasive cervical cancer is significantly reduced, with the reduction persisting through long-term follow-up, according to a study published online Feb. 25 in The BMJ.Shiqiang Wu, from the Karolinska Institutet in Stockholm, and colleagues examined the long-term risk for invasive cervical cancer after receiving the quadrivalent HPV vaccine and how risk varies by time since vaccination. A total of 926,362 girls and women residing in Sweden between 2006 and 2023 were included. The participants were born in 1985 to 1988 (opportunistic cohort), 1989 to 1992 (subsidized cohort), 1993 to 1998 (catch-up cohort), or 1999 to 2001 (school-based cohort).Overall, 365,502 (39.5 percent) girls and women received at least one dose of the quadrivalent HPV vaccine. The researchers identified 930 cases of invasive cervical cancer: 97 in vaccinated and 833 in unvaccinated individuals. The overall fully adjusted incidence rate ratio was 0.21 for participants vaccinated before 17 years of age versus the unvaccinated group, with protection sustained for 13 to 15 years after vaccination (incidence rate ratio, 0.23). The overall fully adjusted incidence rate ratio was 0.63 for individuals vaccinated at 17 years or older compared with the unvaccinated group, with significant reductions in incidence seen during years 10 to 12 and 13 to 15 after vaccination (incidence rate ratios, 0.54 and 0.23, respectively). After adjustment for covariates, the school-based cohort had a lower risk for cervical cancer compared with the opportunistic cohort (incidence rate ratio, 0.28)."We found sustained risk reduction of invasive cervical cancer after quadrivalent HPV vaccine. No indication of waning protection was observed among the vaccinated population," the authors write.Abstract/Full Text.Sign up for our weekly HealthDay newsletter