Changes to cervical screening in Wales: how does it affect Yorkshire?

Changes to the cervical screening programme in Wales have hit the headlines in early 2022. We look at what has changed, why, and how it affects those invited to screening in Yorkshire.

Previously, all people in the UK registered with a GP surgery as being female and aged between 25 and 49 were invited for cervical screening every 3 years, with those aged 50 to 64 invited every 5 years.

This is still the case in England and Northern Ireland, however the cervical screening programme in Wales has changed so that, from January 2022, everyone between the ages of 25 and 64 will be invited to screening every 5 years. This approach has been in place in Scotland for nearly two years.

The change has been introduced so that screening can be personalised based on an individual’s risk. Although the time between screenings will increase for those at low risk of cancer, those at highest risk of cervical cancer will have access to more regular screening. It means they will be monitored more closely than they would have been under the previous system.

The change is a result of significant advances in the way cervical samples are tested, and it is expected to lead to more cervical cancer cases being prevented.

Because cervical screening is now based upon human papillomavirus (HPV) testing, it is safe to extend the time between screening appointments for those who do not have any evidence of HPV in their cervix.

Cervical screening used to involve looking at samples taken from the cervix under a microscope and checking for any abnormal changes in cells. However, at the end of 2019, the screening method was changed to ‘HPV primary testing’ in England, Wales and Scotland.

Almost all cases of cervical cancer are caused by HPV, a common virus spread through any sexual contact. 8 in 10 men and women will have HPV in their lifetime, often without realising it as there are no signs or symptoms.

The ‘HPV primary testing’ method checks samples taken from the cervix for HPV first, rather than immediately looking for changes in the cells. Because HPV causes 99% of all cervical cancers, it’s a much more sensitive method for identifying those at risk.

If HPV is found, further tests are done on the sample to check for abnormal cell changes. If there are abnormal changes, it’s possible to remove them so that cervical cancer doesn’t develop.

Scientists estimate it takes an HPV infection around 10-15 years to lead to abnormal changes to cervix cells.

If someone tests negative for HPV, the chances of them developing any abnormal cell changes in the cervix within 3 years is extremely low. Their chances of developing abnormal cell changes within 5 years are still very low, because these changes develop so slowly.

So, with HPV testing, it’s now possible to extend the time between screening invitations from 3 years to 5 years for those who test HPV-negative, without a significant increase in their risk of developing abnormal cell changes in their cervix.

People who test positive for HPV but do not have abnormal cell changes are invited for further screening after 1 year (for a maximum of 3 years) and the sample goes through the same process, being checked for HPV and then, if positive, being checked for abnormal cells. After 3 years, if the individual is still HPV-positive with no abnormal cells detected, they will automatically be invited for a test called a ‘colposcopy’. This looks more closely at the cervix through a microscope.

Those who have had abnormal cells treated are also regularly monitored.

It is important to note that cervical cancer is rare, and the change made in Wales will ensure that people at the highest risk are identified and monitored effectively while allowing those who are currently at low risk less regular monitoring.

For now, nothing is changing for those invited for cervical screening in Yorkshire or the rest of England. The changes only affect those living in Wales.

These changes follow recommendations of the UK National Screening Committee, which advise cancer screening programmes in all four nations of the UK. Similar changes were introduced in Scotland at the same time as ‘HPV primary testing’ started there in March 2020.

We expect these changes to be introduced in England at some point, so those living in Yorkshire will also switch to being invited every 5 years, unless they are HPV-positive and screened more regularly. However, we don’t yet know when this might happen.

Research shows that the new approach offers 60–70% greater protection against cervical cancer compared to the old process. Because testing for HPV infection is better at finding abnormal cell changes, and these changes can take 10-15 years to happen, a number of large clinical trials across Europe have shown that it is safe to extend the screening interval from 3 years to 5 years, for those who have a negative HPV test result.