The study, published in the British Journal of Cancer, found high uptake of the HPV vaccine in young women is strongly associated with a reduction of low- and high-grade cervical abnormalities.
Researchers from Health Protection Scotland and the University of Strathclyde analysed colposcopy data from young women aged 20-21, who received the vaccine during the ‘catch-up campaign’ of the Scottish Cervical Screening Programme. The catch-up campaign ran from 2008 to 2011 and targeted girls aged 13-18.
The data were used to determine the early impact of the immunisation programme on pre-cancerous changes in the cervix.
Researchers found that three doses of the bivalent HPV vaccine were associated with a decrease in incidence of CIN grades 1, 2 and 3. Although not considered cancerous itself, CIN has the potential to develop into cervical cancer.
Previous studies have shown that the HPV vaccine is strongly associated with a reduction in both HPV 16 and 18, linked to at least 70% of cervical cancers.
Scotland has seen uptake of the HPV vaccine maintained at over 90% in girls aged 12-13 since 2008.
Scotland switched from the bivalent vaccine Cervarix to use the quadrivalent vaccine Gardasil in September 2012, along with the rest of the UK. Gardasil protects against strains 16 and 18, as well as 6 and 11, which cause genital warts.
Co-author Dr Kim Kavanagh from the University of Strathclyde said: ‘To our knowledge, this is one of the first studies to show a reduction of pre-cancerous cells associated with the HPV vaccine at the population level. These data are very encouraging for countries that have achieved high HPV vaccine uptake.’
The authors said further study was required to determine whether two doses of the vaccine, as has now been approved in the UK, would have a similar effect.
Dr Kevin Pollock, senior epidemiologist at Health Protection Scotland, said: 'These findings are very exciting and demonstrate that high uptake of the HPV vaccine is associated with a significant reduction of low and high-grade cervical abnormalities in young women in Scotland.'
A similar study in Australia in 2011 found cervical abnormalities in teenage girls fell by half just three years after HPV vaccination began.
Cervical cancer is the second most common cancer in women under 35 years old.