Women who received the HPV vaccine before age 17 reduced their risk of cervical cancer by 88% compared to unvaccinated women, new study found.
“This is the first time that we, on a population level, are able to show that HPV vaccination is protective not only against cellular changes that can be precursors to cervical cancer but also against actual invasive cervical cancer,” said corresponding author Jiayao Lei, PhD, researcher, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Sweden, in a press release. “It is something we have long suspected but that we are now able to show in a large national study linking HPV vaccination and development of cervical cancer at the individual level.”
Previous research has shown that the HPV vaccine is effective in preventing high-grade cervical lesions, but there is a lack of large population-based studies that have examined the association between the HPV vaccine and the risk of invasive cervical cancer, the most severe form of the disease.
In this study, published online October 1, 2020, in the New England Journal of Medicine, Lei and colleagues used nationwide Swedish health registers to follow approximately 1.7 million Swedish women aged 10-30 years for 11 years; researchers controlled for age at follow-up, calendar year, county of residence, and parental characteristics, such as education, income, birth country, and disease history.
Overall, >500 000 women were vaccinated against HPV, the majority before they turned 17-years-old. Nineteen women who received the HPV vaccine were diagnosed with cervical cancer vs 538 unvaccinated women, corresponding to 47 and 94 women per 100 000, respectively.
Also, the results showed that girls who received the HPV vaccine before age 17 reduced their risk of invasive cervical cancer by 88% vs unvaccinated girls, and women vaccinated between ages 17-30 reduced their risk by 50% vs unvaccinated women.
“In conclusion, our study shows that HPV vaccination may significantly reduce the risk of cervical cancer, especially if completed at an early age,” said coauthor Pär Sparén, PhD, professor, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, in the same press release. “Our data strongly support continuing HPV vaccinations of children and adolescents through national vaccination programs.”