Cervical cancer risk factors

Each year, more than 13,000 women in the United States are diagnosed with cervical cancer.

No woman knows if or when she will receive a diagnosis of cervical cancer, but routine Pap testing may help detect abnormal changes to the cervix before cancer has a chance to develop. That is why women who do not regularly have a Pap test are at increased risk of developing cervical cancer.

What causes cervical cancer?

Cervical cancer forms when the DNA in cells in the cervix mutate or change. In some cases, these mutated cells grow out of control, forming a tumor in the cervix.

Cervical cancer is almost exclusively caused by a human papillomavirus (HPV) infection, although not all women with an HPV infection will develop cervical cancer. Girls and young women who are treated with the HPV vaccine have a significantly reduced risk of developing cervical cancer later in life.

Known risk factors for cervical cancer include:

Lifestyle

Sexual history: Certain types of sexual behavior are considered risk factors for cervical cancer and HPV infection, including early onset of sexual activity (beginning in the early teen years), sex with multiple partners, and sex with someone who has had multiple partners.

Smoking: A woman who smokes doubles her risk of cervical cancer, because carcinogens that are inhaled are partly excreted in cervical mucus and bathe the cervix.

Other conditions

HPV: Although HPV often causes cancer, having HPV does not mean you will get cancer. For most women, the HPV virus goes away on its own, or the women undergo treatments to remove the abnormal cells. HPV is a skin infection, spread through skin-to-skin contact with a person who has the virus.

Weakened immune system: In most people with healthy immune systems, the HPV virus clears itself from the body within 12 to 18 months. However, people with HIV are at an increased risk, as are those who are chronically immunosuppressed, such as transplant patients or those with another chronic or acute illness.

Diethylstilbestrol (DES): Women whose mothers took DES, a drug given to some women to prevent miscarriage between 1940 and 1971, have a higher risk of developing cervical cancer.

Additional facts about HPV:

• There are more than 100 types of HPV, 30 to 40 of which are sexually transmitted.
• Of these, at least 15 are high-risk HPV strains that can cause cervical cancer. The others may genital warts or cause no symptoms.
• Up to 80 percent of women and men will contract HPV in their lifetime. For most people with a healthy immune system, the virus disappears from the body within one to three days. Some high-risk strains carry a much higher risk of causing cervical cancer.
• A healthy immune system will usually kill the HPV virus, including the high-risk types of HPV.
• Only a small percentage of women with high-risk HPV develop cervical cancer.

Next topic: What are the symptoms of cervical cancer?