Screening woman for cervical cancer every five years instead of every three could still prevent as many cancer cases, according to a new study.
Experts at King's College London (KCL) collected data from 1.3 million women in England. They found that by screening women for traces of human papillomavirus (HPV), which is found in 99% of all cervical cancers, the intervals between tests could safely be extended.
Dr Matejka Rebolj, the leader author of the report, said the results were "very reassuring".
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To know...
Currently women in England aged 25 to 49 are invited for cervical screening every three years, while those aged 50 to 64 are invited every five years.
Dr Rebolj said: "They build on previous research that shows that following the introduction of HPV testing for cervical screening, a five-year interval is at least as safe as the previous three-year interval.
"Changing to five-yearly screening will mean we can prevent just as many cancers as before, while allowing for fewer screens."
Before 2019, cytology tests, otherwise known as smear tests, checked cervical cells for abnormalities first, but now samples taken during cervical screening are tested for HPV first.
The team said that because HPV infection comes before having abnormal cells, HPV testing detects more women at risk of cervical cancer.
Researchers from KCL, the University of Manchester, and the NHS analysed data from the NHS Cervical Screening Programme in England and followed those attending screening for two rounds, the first from 2013-2016 with a follow up by end of 2019.
They found that people under 50 eligible for screening who had a negative HPV screen in the first round had a lower risk of detection of CIN3+ in the second round compared to cytology tests.
The study found that 1.21 in 1,000 people had a detection of CIN3+ after a negative HPV screen compared to 4.52 in 1,000 people after a negative cytology.
Dr Rebolj said: "This monumental study relied on a multidisciplinary team including those in the NHS Cervical Screening Programme in England, working with women undergoing screening and their samples, and our academic partners.
"This partnership provides evidence that will best serve the millions of women invited for screening throughout most of their adult lives.
"These promising results show most women and people with a cervix do not need to be screened as frequently as they are now."
Michelle Mitchell, Cancer Research UK's chief executive, said: "This large study shows that offering cervical screening using HPV testing effectively prevents cervical cancer, without having to be screened as often.
"This builds on findings from years of research showing HPV testing is more accurate at predicting who is at risk of developing cervical cancer compared to the previous way of testing.
"As changes to the screening programmes are made, they will be monitored to help ensure that cervical screening is as effective as possible for all who take part.
"It's important to remember, screening is for people without symptoms. So, if you notice any unusual changes for you, do not wait for a screening invitation - speak to your doctor."