It is thought that as many as 9 out of 10 cancers of the cervix may be caused by a virus, called HPV (human papilloma virus) which is an infection and can be passed on through sexual contact.

There are more than 20 different types of HPV. Only certain types, such as 16, 18, 31 and 33 (known as 'high risk' types) seem to be associated with the development of cancer of the cervix.

Many women have HPV infection but do not develop cervical cancer, as it often goes away by itself. The infection often does not cause any symptoms and it doesn’t need any specific treatment.

In some women, the infection stays and may make the cells in the cervix  change and become abnormal if it is not treated. Over many years, these changes can lead to the development of cancer.

Having regular cervical smears is very important because changes in the cells in the cervix can be detected at an early stage, and abnormal pre-cancerous cells can be got rid of by a simple operation before they develop into cancer.