Almost four out of ten women aged 25-34 are failing to attend routine smear tests in England.

On the day government figures showed that 400,000 significant abnormalities of the cervix have been spotted in 20 years of screening, statistics obtained by the Liberal Democrats suggest a large proportion of young women are still not taking the risk of cancer seriously. The results improve in the 35-39 age group, in which 72 per cent of women have undergone a smear test in the last three-and-a-half years.

The figures are a blow to Alan Johnson, the Health Secretary, who hailed the importance of regular checks during a visit today to a London hospital to mark the 20th anniversary of NHS screening.

Together with breast screening, which has led to the detection of more than 100,000 cases of cancer since screening began, it is estimated that cervical examinations have saved 5,900 lives a year since they began in 1988.

Mr Johnson met patients and staff at the the breast screening unit at King's College Hospital. During the visit, he heard about the difficulties of reaching women from poorer communities and black and minority ethnic groups: “I live in south London so I do understand the make-up of the population here and it didn’t surprise me where there was very high take-up and where there was very low take-up.

“But what I was encouraged by is the amount of focus that there is on that and indeed that the hard core, the most difficult to reach, is down to about 5 per cent."

Mr Johnson said: "The 20th anniversary of the NHS breast and cervical screening programmes is an ideal opportunity to remind people about the vital role screening plays in prevention and early diagnosis.

“Despite all the progress, we are determined to do more. We have introduced a new HPV vaccine to help reduce cervical cancer, will extend the breast cancer screening programme to all women aged 47 to 73 by 2012 and are investing £100 million in new digital mammography equipment.

“But the benefits of this investment cannot be fully recognised if people are unaware of how important screening is."

Julietta Patnick, director of NHS cancer screening programmes, said: “The NHS cancer screening programmes are internationally recognised as world-class services. But there are still challenges to overcome. We continue to support the local NHS in increasing awareness amongst those less likely to accept screening invitations.”

Cancer charities stressed that the screening programmes will need more resources to meet challenges, including that posed by an ageing population. Richard Davidson, of Cancer Research UK, said: "The NHS should be justly proud but more work needs to be done."

Jeremy Hughes, chief executive of Breakthrough Breast Cancer, said that the breast screening programme had to date offered “an unmatched, life-saving service which enables breast cancers to be detected before they can be seen or felt by hand".

But he warned that the service was likely to face increased demand in the future: “Due to an ageing population, a 20 percent increase in the number of women invited for screening by 2025 is already forecast - and this will rise further as the programme is extended to include women aged 47-50 and 70-73.

“The Government needs to ensure that sufficient resources are in place to meet the demographic challenge ahead. It must also work hard to get across to all sections of the community the vital message that screening saves lives.”

SCREENING BY THE NUMBERS

More than 70 million screenings for breast and cervical cancer have taken place in England since the NHS programmes began in 1988

Over 100,000 cases of breast cancer have been detected, equating to more than 100 per week

400,000 "significant abnormalities" of the cervix have been found

18 million sets of mammograms have been taken

Breast screening is thought to save 1,400 lives every year

Cervical screening is estimated to save 4,500 lives per year

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