How does HPV cause cervical cancer?

High risk types of the Human Papilloma Virus (HPV) cause 99% of cases of cervical cancer.

Your body’s immune system fights off most HPV infections naturally, but about one in 10 infections are harder to get rid of.

Sometimes HPV gets into the lining of a woman’s cervix, the entrance of the womb. It may stay in the cervix for several years without doing any harm.

But in a few cases the virus damages cells in the cervix and stops them repairing themselves. If these damaged cells are left untreated they can develop into cervical cancer. Cancerous tumours come from damaged, abnormal cells that multiply out of control.

Find out more about cervical cancer.

There are lots of different types of HPV, but only a few damage cervical cells and increase the risk of cancer. These are called high risk types and there are around 15 of them.

Two of the more common high risk types are HPV types 16 and 18. These are responsible for 70% of cases of cervical cancer.

Women who have high-risk types of the virus are more likely to develop abnormal cervical cells and are at greater risk of cervical cancer. However, most women who acquire HPV, including high-risk HPV, will not be affected by it.

How HPV can lead to cervical cancer

This diagram shows how HPV infection can lead to cervical cancer.

The abnormal cells can be detected at screening and, if necessary, can be treated, which is why it is vital all women attend for regular cervical screening.

How to protect yourself

Cervical screening can spot when an HPV infection damages cells in the cervix which can increase the risk of cancer developing. Once abnormal cells are detected, they can be checked regularly and if appropriate, removed.

This is why having regular cervical screening is important.

Find out more about the benefits of cervical screening.

The new HPV vaccine protects against infection from high risk HPV types 16 and 18 and means there’s less chance of abnormal cells developing in the first place.

HPV is passed on through intimate skin-to-skin contact with someone who has the virus. Practising safer sex can help prevent the virus being spread and reduce the risk of cervical cancer.