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Benefits and limitations of screening

1. Why you are offered a free cervical screening test
2. What causes abnormal cells in the cervix
3. Cervical cancer
4. Benefits and limitations of screening
5. The CervicalCheck screening programme

Benefits of screening

Regular cervical screening:

  • saves lives
  • can find abnormal changes in the cells of the cervix when they are easier to treat
  • helps find abnormal cell changes before symptoms develop

Finding abnormal cells early is the best way to prevent cervical cancer. This is why having regular screening tests is important.

Since CervicalCheck started in 2008:

  • more than 3 million screening tests have been done
  • the number of women who develop cervical cancer has fallen
  • over 100,000 cases of abnormal cervical cells have been detected and treated - many of these could have developed into cancer if not detected through screening

Limitations to screening

The main limitations of screening are:

  • Cervical screening will not prevent all cases of cervical cancer.
  • Some women will still develop cervical cancer despite regular screening.
  • Some abnormal cell changes may be missed.
  • Screening will not find every abnormal cell change

Why are abnormalities missed?

Abnormalities will sometimes be missed because:

  • sometimes they do not look much different from normal cells
  • there may be very few abnormal cells in the sample
  • the person reading your sample may miss the abnormality (this happens occasionally, no matter how experienced the reader is)

No test in any screening programme will find every woman who has abnormal cervical cells. If 1,000 women are screened:

  • About 20 women will have abnormal cervical cells.
  • About 15 of these women will have these cells found through screening.
  • About 5 women will not have these cells found through screening and may develop cervical cancer.

Sometimes test results are inaccurate. We call these results 'false positives' and 'false negatives'.

Fortunately, cervical cancer takes many years to develop. So this means that abnormal cells missed on one screening test can be found on the next one. 

This is why you should always attend your cervical screening test when it's due.

Negative experiences

Aside from the limitations of screening, negative experiences of screening might include:

  • potential discomfort, embarrassment or (less commonly) pain during your screening test
  • anxiety in waiting for your results
  • side-effects or complications due to treatment after colposcopy