How Can You Prevent Cervical Cancer?
Cervical cancer is one of the most preventable types of cancer for these reasons:
It has risk factors that are within your control.
It has a recommended screening test in the Pap test, which can find the cancer early or in precancerous stages.
Two vaccines that may help to decrease the risk for cervical cancer are available for girls and young women. One of them is also available for boys and young men.
The most important risk factor for cervical cancer is having certain types of the human papillomavirus (HPV), one of the most common sexually transmitted diseases in the United States. More than 100 strains of HPV have been identified, but only about 30 can be transmitted through sexual contact and only about 15 are implicated in cervical cancer and the condition that precedes it, cervical intraepithelial neoplasia grade 3. All strains of HPV can cause non-cancerous warts.
HPV is most common in women and men in their late teens and early 20s. At least 50 percent of sexually active men and women acquire genital HPV infection at some point in their lives.
HPV is usually transmitted through vaginal, oral, or anal sexual intercourse with a person who has the virus. It can also be transmitted through skin-to-skin contact that does not involve penetration of the anus or vagina. Because genital warts may not always be present or visible, it's impossible to tell just by looking if a person has genital HPV. Also, a person may not know he or she has HPV, because there may be no symptoms.
Most HPV infections go away on their own within months to a few years and don't cause cancer. If the infection does not clear up on its own, it takes years to progress to the precancerous stage or to invasive cancer. Experts think that other factors also must be present for cancer to develop.
Preventing HPV is a major step toward preventing cervical cancer. Two vaccines are available to protect against HPV. Both are given as a series of three injections given over a six-month period. They protect against HPV strains 16 and 18, which cause about 70 percent of cervical cancers, and one also protects against types 6 and 11, which cause most genital warts.
The vaccines are effective only if given before an infection with HPV, so one of them should be given before a person becomes sexually active.
Because the vaccines are new, experts don't know how long they will continue to offer protection. Studies so far, however, have shown that the vaccines continue to be effective against HPV 16 for several years.
The vaccines are recommended for all girls between ages 11 and 12, and girls as young as age 9 can receive one of the vaccines. Girls and women 13 to 26 years old who have not received the vaccine should be allowed to catch up on vaccination. The vaccine is not routinely recommended for women older than 26.
The HPV4 (quadrivalent) vaccine is recommended for all boys between ages 11 and 12. Those 13 to 26 years old who have not received the vaccine should be allowed to catch up on vaccination. Males aged 22 to 26 may also be vaccinated.
Condoms, if used correctly and consistently, also may help protect you from getting HPV. The virus, however, can be spread through skin-to-skin contact with any infected part of the body, including the skin in the genital area that cannot be covered by a condom. Condoms do help prevent chlamydia infection, which has been linked to an increased risk for cervical cancer.
Importance of Pap tests
If you are already infected with one of the covered HPV strains, the HPV vaccine cannot protect you from the effects of that strain, although it will protect you against the others that are covered. The vaccines also will not protect against infection with any other HPV strains. Because of these reasons, regular cervical cancer screening is still important.
Pap tests can detect precancerous changes in the cells of the cervix before they become cancer. They can also detect cervical cancer in its early stages, when it can be treated most easily. So getting regular Pap tests with or without HPV tests gives you a better chance of preventing cancer. Occasionally, the pelvic exam that is often done along with Pap tests can also help detect some cancers of the uterus and other parts of the female reproductive system.
According to the American Cancer Society (ACS), all women should have Pap tests starting at age 21. Women between ages 21 and 29 should have a Pap test every three years. Women between the ages of 30 and 65 should have a Pap test plus an HPV test - called "co-testing" - every five years. This is the preferred approach, but it is also acceptable to continue to have Pap tests alone every three years. Women who have an increased risk for cervical cancer because of a weakened immune system or other risk factors may need more frequent screening and should discuss this with their health care provider.
Women older than 65 who have had regular screening with normal results should not be screened for cervical cancer. Once screening is stopped, it should not be started again. A woman who has had a hysterectomy with removal of the cervix for reasons not related to cervical cancer and who has no history of cervical cancer or serious pre-cancer should not be screened. A woman who has been vaccinated against HPV should still follow the screening recommendations for her age group.
Other risk factors
Although HPV infection is the main risk factor for cervical cancer, not all women with HPV get this cancer. The ACS says that other risk factors may be involved that increase the chances of developing cervical cancer:
Smoking. Smoking doubles the risk for cervical cancer, the ACS says.
HIV. Although the virus that causes AIDS is different from HPV, it still raises the risk for cervical cancer. Having a weakened immune system due to other reasons, such as certain medications or a recent organ transplant, is also a risk factor for cervical cancer since it interferes with your body's ability to fight HPV infection.
Chlamydia. Chlamydia is another sexually transmitted disease (STD). Some studies have found a connection between this infection and increased risk for cervical cancer.
Diet and weight. Women who are overweight or eat a diet low in fruits and vegetables seem to be at higher risk for cervical cancer.
Oral contraceptives. The ACS says that using birth control pills for five or more years puts a woman at higher risk for cervical cancer, but the risk goes down again over time once the pills are stopped.
Many children. A woman who has had many full-term pregnancies is at higher risk.
Poverty. Women of low income are at greater risk, possibly because they cannot afford good preventive health care. Some local health clinics do provide low-cost or free screening programs for cervical cancer.
Family history. Having a mother or sister with cervical cancer puts you at higher risk.