HPV vaccines offer strong protection against cervical cancer, new reviews reveal
Two fresh Cochrane reviews by UK researchers present consistent, robust evidence that human papillomavirus (HPV) vaccination helps prevent cervical cancer, significantly lowers high-grade precancerous lesions, and is not linked to serious adverse events—especially when given to young people who have not yet been exposed to the virus. The findings emphasize the value of vaccinating in early adolescence.
Scope and data
These reviews draw on both randomized controlled trials (RCTs) and large population studies, analyzing data from more than 132 million individuals worldwide.
80% drop in cervical cancer
A population-level analysis, drawing on 225 studies across 46 countries, found an 80% reduction in cervical cancer among girls vaccinated by age 16 (risk ratio [RR] = 0.20). Protection was smaller for those vaccinated later in adolescence or as adults.
The review also provides moderate-certainty evidence that vaccination lowers rates of precancerous cervical lesions and the occurrence of anogenital warts.
Moreover, the studies found no evidence that HPV vaccination is associated with well-known harms such as infertility, chronic fatigue syndrome (myalgic encephalomyelitis), Guillain-Barré syndrome, or complex regional pain syndrome.
RCTs of four WHO-approved vaccines
A separate analysis of randomized trials evaluated four HPV vaccines—Cervarix, Gardasil, Gardasil-9, and Cecolin—across 60 trials involving 157,414 participants. Although the trial durations were not long enough for cancers to develop, vaccination reduced high-grade vaccine-matched precancerous cervical lesions by 60% (RR = 0.40) in females aged 15 to 25 after six years.
A comprehensive comparison across 39 studies showed no difference in the rate of serious adverse events between vaccine and control groups, up to 72 months of follow-up (RR ≈ 1).
Geographic gaps and the call for longer-term research
Cochrane’s press release notes that these reviews are the most comprehensive and up-to-date synthesis on HPV vaccination to date. Yet, gaps remain. Most data come from high-income countries, so more research is needed in lower- and middle-income regions where cervical cancer screening is less established. The authors also urge longer-term studies to monitor outcomes beyond early adulthood.
Senior author Jo Morrison, DPhil, gynecologic oncology consultant at Somerset NHS Foundation Trust and honorary associate professor at the University of Exeter, emphasizes: longer-term data will further clarify how HPV vaccination protects against cancer across a lifetime. While current evidence demonstrates a beneficial impact on cervical cancers, which typically develop earlier in life, it may take decades to fully understand the vaccine’s impact on vulvar, peri-anal, penile, and head-and-neck cancers that often arise later.
