Cervical cancer causes and risk factors

Cervical cancer develops in a woman’s cervix, the lowest part of the uterus. While all women age 21 and older may be screened for this disease, some have an elevated risk and would benefit from routine checkups.

HPV is the main cause of cervical cancer

Nearly all cervical cancer cases are related to HPV, a group of common viruses that may spread from person to person during sexual contact, including vaginal, anal and oral sex.

HPV is very common. In fact, most people will get it at some point in their lifetime, and many won’t recognize it because it usually lacks symptoms. Most of the time, the patient's body will fight off and clear up the HPV virus on its own. However, sometimes the infection doesn’t go away, and some types of HPV may eventually lead to cancer. 

Out of more than 200 strains of HPV, some are high-risk types strongly linked to cancer, while others are considered low risk. Also, HPV may cause different  cancers, including cancer of the vulva, vagina, penis, anus, mouth and throat. 

About 40 types of HPV have been known to target the cervix in particular. Over time, certain types may cause changes in the cervix that eventually lead to the development of precancerous and cancerous cells. 

Currently, there’s no cure for HPV, but regular screenings may help catch cervical cancer early. Screenings include a Papanicolaou (Pap smear) test or an HPV test. If precancerous cells are found, treatments are available, so not getting suggested screenings for early detection of HPV is in itself a risk factor for developing cervical cancer.

Also, HPV vaccines may significantly reduce the risk of developing cervical cancer by protecting women from key types of the virus. These vaccines have age restrictions, so check with a doctor to determine the eligibility requirements.

What causes cervical cancer besides HPV?

In addition to HPV, several other known risk factors may increase a woman's chance of developing cervical cancer.

Chlamydia

This sexually transmitted infection may create an environment that helps HPV grow and thrive. Because chlamydia often lacks symptoms, ask the doctor about getting tested. This is especially true for women who are sexually active and not in a monogamous relationship. 

Sexual history

Certain factors related to sexual activity may increase the risk of developing cervical cancer, including becoming sexually active before age 18 and having multiple sexual partners. These factors likely play a role in elevating cervical cancer risk because they raise the odds that a woman will be exposed to HPV.

A weakened immune system

Women who have immune system deficiencies may be more at risk of developing an HPV infection and cervical cancer. Common causes of immune system deficiency include taking immunosuppressant drugs (such as after an organ transplant, or to treat autoimmune diseases)  and having the human immunodeficiency virus (HIV). When the immune system isn’t functioning properly, the body is more susceptible to infections like HPV and is less able to fight off cancer cells and block their growth.

Smoking

Smoking cigarettes gives women twice the risk of developing cervical cancer compared with nonsmokers. Breathing in secondhand smoke also poses a higher risk.

Pregnancy history

The risk of developing cervical cancer is higher among women who have given birth to three or more children. There are a few potential reasons for the role of pregnancy in cervical cancer risk:

• Women who have multiple babies may be more sexually active and therefore more exposed to HPV. 
• Pregnant women may be more vulnerable to HPV infection or cancer, potentially because of hormonal changes or a weakened immune system.
• Age may also be a factor: Women who have a baby before age 20 are at higher risk than those who wait until after 25.

Diet

There’s growing evidence that not eating enough vegetables and fruits may increase the risk for cervical cancer, among other health issues.

Birth control pills

Taking oral contraceptives for five or more years gives women a higher risk of developing cervical cancer compared with women who have never taken birth control pills. That risk for cervical cancer increases over time.

Stopping oral birth control begins to lower the risk of cervical cancer, and the risk returns to normal over a 10-year period.

Exposure to DES in the womb

From 1940 to 1971, some women in the United States were given the drug diethylstilbestrol, or DES, to prevent miscarriage, but the drug often had serious consequences for their babies. Women exposed to DES while in the womb have a higher risk of developing a rare type of cancer called vaginal or cervical clear-cell adenocarcinoma. This particular risk ended for anyone born after 1971, the year the U.S. Food and Drug Administration banned its use during pregnancy.  

Family history

Having a first-degree relative—a mother or sister—with cervical cancer puts women at a higher risk than someone with no family history of the disease.

 

Cervical cancer prevention

 

Although some cervical cancer risk factors (like family history) can't be changed, women can take some steps that may help lower the risk of developing this disease:

• Get the HPV vaccination as part of the routine vaccination schedule and based on the care team's recommendations.
• Quit smoking or avoid picking up the habit.
• Don't skip or avoid cervical cancer screenings. By following the recommended screening schedule, precancerous cells may be identified and addressed more quickly.
• Use condoms during sexual activity.
• Consume a balanced diet, including fruits and vegetables.