Risks and causes

  • Anything that increases your risk of getting a disease is called a risk factor.
  • Having one or more risk factors does not mean you will get cervical cancer.
  • Human papilloma virus (HPV) is a major cause of cervical cancer practising safe sex can reduce the chances of HPV infection. Vaccines are available to prevent HPV.
  • Smoking increases the risk of cervical cancer and makes it harder to treat abnormal cells in the cervix.

Cervical cancer is the 14th most common cancer in females in the UK.

Anything that increases your risk of getting a disease is called a risk factor. Different cancers have different risk factors.

Having one or more risk factors does not mean that you will definitely get cervical cancer.


Cervical cancer is more common in younger women. More than half of the cervical cancer cases in the UK each year are diagnosed in women under the age of 45.

Human Papilloma Virus (HPV) infection

The human papilloma virus (HPV) is a major cause of the main types of cervical cancer.

HPV is common. Most sexually active people come into contact with HPV during their lifetime. But for most the virus causes no harm and goes away on its own.

Types of HPV

There are many different types of HPV. Most are harmless but some cause genital warts, and others cause changes that can develop into cancer. As well as cervical cancer, HPV can cause anal, vaginal, vulval, penile and some types of mouth and throat cancers. HPV can be passed on through close skin to skin contact, usually during sexual activity.

Around 12 types of HPV are considered high risk for cancer of the cervix. Two of these types (HPV 16 and HPV 18) cause about 7 out of 10 (70%) cervical cancer cases.

For most people, the immune system clears the HPV infection within 2 years. But sometimes this doesn't happen. If you have a long lasting (persistent) infection with a high risk type of HPV, you are more at risk of developing cervical cancer.


Practising safer sex by using barrier methods like condoms will reduce your risk of getting HPV and passing it on. But they won’t protect you completely. Practising safer sex will also help to protect you against many sexually transmitted diseases.


There are now vaccines to prevent HPV infection. All girls aged 12 or 13 in the UK are routinely offered the HPV vaccine at school. These vaccines protect against the types of HPV that are most likely to cause cervical cancer. But they don't protect against all types. So you still need to take part in cervical screening, even if you have had the HPV vaccine.

Human immunodeficiency virus (HIV)

Having human immunodeficiency virus (HIV) or AIDS increases the risk of developing cervical cancer. This risk might be reduced in women who are having treatment for HIV.

Other sexually transmitted infections

The risk of cervical cancer may be increased in women who have a sexually transmitted infection (STI) alongside HPV.

Women with both HPV and chlamydia (pronounced klah-mid-ee-ah), might have a higher risk of cervical cancer.

Smoking tobacco

Smoking tobacco increases your risk of getting cervical cancer. The risk increases with the more cigarettes you smoke a day and the younger your age when you start smoking.

Smoking also makes it harder to treat abnormal cells on your cervix.

It’s never too late to stop smoking but the sooner you stop the better.

Contraceptive pill

1 in every 10 cases of cervical cancer is linked to taking the contraceptive pill.

Taking the pill for more than 5 years increases the risk of cervical cancer. The increased risk begins to drop as soon as you stop taking it. After 10 years the risk is the same as if you had never taken it.

The pill can also slightly increase the risk of breast cancer. But it is important to know that taking the pill can help reduce the risk of womb and ovarian cancers.

How many children you have, and when

Women who have had children are at an increased risk of cervical cancer compared to those who haven't.

Having your first baby before the age of 17 also gives a higher risk, compared to women who had their first baby after the age of 25. The reasons for this are unclear. 

Family history

You have an increased risk of cervical cancer if your mother, sister or daughter has had cervical cancer. We don’t know whether this is linked to faulty genes, or whether it is due to common shared factors like smoking.

Previous cancer

You have an increased risk of cervical cancer if you have had cancer of the:

  • vagina
  • vulva
  • kidney
  • urinary tract (includes the bladder and the tubes from the kidneys to the bladder)

One of the reasons for this might be previous radiotherapy treatment.

For detailed information on cervical cancer risks and causes

Other possible causes

Stories about potential causes are often in the media and it isn’t always clear which ideas are supported by evidence. There might be things you have heard of that we haven’t included here. This is because either there is no evidence about them or it is less clear.

Cervical screening

Regular cervical screening can prevent cervical cancer by picking up abnormal cell changes in the cervix. These changes could lead to cancer if left untreated. 

Cervical screening is available for women between the ages of 25 to 64.

  • List of classifications by cancer sites with sufficient or limited evidence in humans
    International Agency for Research on Cancer (IARC)
    (Accessed May 2020)

  • Increased regression and decreased incidence of human papillomavirus-related cervical lesions among HIV-infected women on HAART
    DH Adler and others
    AIDS, 2012. Volume 26, Issue 13

  • Chlamydia Trachomatis Infection-Associated Risk of Cervical Cancer: A Meta-Analysis
    H Zhu and others
    Medicine, 2016. Volume 95, Issue 13

  • Persistent human papillomavirus infection and smoking increase risk of failure of treatment of cervical intraepithelial neoplasia (CIN)
    NN Acladious and others
    International Journal of Cancer, 2002. Volume 98, Issue 3

  • Cancers attributable to exposure to hormones in the UK in 2010
    DM Parkin
    British Journal of Cancer, 2011. Volume 105 Supplement 2

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. If you need additional references for this information please contact patientinformation@cancer.org.uk with details of the particular risk or cause you are interested in.

Last reviewed: 
26 May 2020
Next review due: 
26 May 2023

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