Jo Morrison, BM BCh, highlights HPV vaccination to prevent cervical cancer

In an interview with Contemporary OB/GYN, Jo Morrison, BM BCh, consultant gynecological oncologist at the University of Exeter, discussed the robust evidence demonstrating that human papillomavirus (HPV) vaccination directly prevents cervical cancer—moving far beyond a simple association.

Morrison explained that randomized controlled trials (RCTs) and large-scale population studies now offer converging lines of evidence that clearly establish a causal relationship. While observational studies traditionally suggest association only, the consistent direction and magnitude of findings across study types confirm that HPV vaccination fundamentally reduces cervical cancer risk.

Population-level vaccine programs implemented since 2008 provide some of the strongest real-world data. Morrison noted that 225 studies, encompassing approximately 132 million individuals, reveal a striking age-dependent effect. Vaccination before the age of 16 years yields an 80% reduction in cervical cancer incidence, as well as substantial decreases in high-grade cervical intraepithelial neoplasia (CIN).

Emerging evidence also shows declines in vulvar and vaginal intraepithelial neoplasia. Countries with early, high-coverage vaccination programs—particularly Australia, Scotland, and England—now report 0 cervical cancer cases in cohorts vaccinated at ages 12 to 13 years, underscoring the power of vaccinating prior to natural HPV exposure.

Morrison emphasized that RCTs originally underestimated the vaccine’s full impact because most trials excluded individuals aged under 15 years. Younger adolescents could not ethically undergo HPV swabbing or cervical assessments, limiting early trial designs. As a result, RCTs measured outcomes in older age groups more likely to have prior HPV exposure. The much larger effects seen in real-world, early-adolescent vaccination programs therefore represent the vaccine’s true potential.

The optimal vaccination window, Morrison explains, is before the onset of sexual activity—generally between the ages of 8 and 13 years old, depending on country guidelines. The HPV vaccine works by presenting virus-like particles composed solely of viral protein, not live virus. These particles stimulate antibody production that blocks HPV from entering cells during later exposure. Because this mechanism depends on pre-existing antibodies, timing is essential.

To support vaccine uptake, Morrison encouraged clinicians to share clear evidence of both effectiveness and safety. She highlighted that extensive reviews—including investigations into concerns frequently raised on social media—show no increased risk of conditions such as postural orthostatic tachycardia syndrome or paralysis. Importantly, there is “evidence of absence,” not merely absence of evidence, regarding these risks.

Morrison concluded by emphasizing the importance of transparent, bias-minimized research synthesis, such as that conducted by Cochrane. Comprehensive review of published data and clinical study reports strongly supports HPV vaccination as a safe, highly effective cancer-prevention strategy.

No relevant disclosures.

Reference

New research confirms HPV vaccination prevents cervical cancer. Cochrane. November 23, 2025. Accessed December 5, 2025. https://www.eurekalert.org/news-releases/1106620