A vaccine to prevent cervical cancer is safe and effective, a new review has confirmed. 

The human papilloma virus (HPV) vaccine reduces precancerous changes and doesn’t cause serious side effects, according to one of the largest reviews to date. 

Professor Peter Sasieni, a Cancer Research UK-funded cervical screening expert at King’s College London, said he hoped the work would encourage young girls and their parents to take up the vaccination as there is clear evidence that it works. 

Sophia Lowes, from Cancer Research UK, said: “Virtually all cases of cervical cancer are caused by HPV and the HPV vaccine protects against the main types of the virus. By protecting against the infection, we can help prevent abnormal changes in cells in the cervix and ultimately hope to see fewer cases of cancer.”

About 3,100 cases of cervical cancer are diagnosed in the UK each year. But most women with HPV don’t develop cervical cancer. Since 2008, girls aged 11-13 have been offered a vaccination against the two most common ‘high-risk’ types of HPV: HPV 16 and 18. Girls up to the age of 18 can request vaccination through the NHS if they weren’t vaccinated at age 11-13.

Other countries offer the vaccine to girls of different ages.

The review, published in the Cochrane Database of Systematic Reviews, looked at 26 trials across the world, involving over 73,000 women. Most women were under 26 and were monitored for up to eight years after vaccination. 

It found strong evidence that the HPV vaccine effectively protects against changes to cells in the cervix that can become cancer in women aged 15-26. 

In older women, vaccinated between 25 to 45 years of age, the effects of HPV vaccine on precancer are smaller. The researchers suggested this might be due to them having already been exposed to HPV.

HPV vaccination hasn’t been used for long enough to definitively assess an effect on cervical cancer, but these changes are a precursor to the disease. 

Sasieni said the study gives very clear answers, and that it adds to evidence from clinical trials that have shown that the HPV vaccine is safe and effective. 

“Data from populations around the world have already demonstrated that vaccinating teenagers reduces HPV infection and has few, if any, serious side effects,” he said. “This review backs up that evidence.”