HPV: Human Papillomavirus Infection and Cervical Cancer

The human papillomavirus is very common and will infect at least 50% of all people who have sex at some time in their lives. Often, no symptoms appear, and the infection disappears on its own.  However, some types can lead to certain cancers, such as cervical cancer. There are actually more than 100 related viruses in the HPV group.  Each HPV virus is given a number or type. The term "papilloma" refers to a kind of wart that results from some HPV viruses. Of the 100 HPV types, about 60 types cause warts on areas such as the hands or feet. The other 40 or so types of HPV are sexually transmitted and are drawn to the body's mucous membranes; the moist layers around the anal and genital areas.

Not all of the 40 sexually transmitted HPV viruses cause serious health problems. Two HPV viruses cause approximately 70% of all cervical cancers, while two others cause about 90% of genital warts.  Genital warts can look like bumps or cauliflower-like growths.  They can show up weeks or months after exposure to an infected sexual partner, but they rarely become cancerous.

Risk Factors for Cervical Cancer

It usually takes a long period of time for cervical cancer to develop.  HPV causes cells near the cervix to change, which sometimes results in pre-cancer.  A Pap test is the best way to find changes in cervical cells that may be precancerous. Besides the presence of HPV infection, there are several things that can increase the risk of cervical cancer developing.  Any of these risk factors need to be discussed with your physician or midwife:   

• Smoking  - Cigarettes contain many cancer-causing agents.  Some can cause damage to the cervical cells, possibly leading to cervical cancer.  Also, some studies have shown that smoking can accelerate the cervical damage caused by HPV.
• Sexual History - Having multiple sex partners or having sex with someone who has had many sexual partners may increase your risk of developing HPV and therefore cervical cancer.  Having sex at an early age also increases the risk for cervical cancer.
• HIV Infection - Women infected with HIV are at a greater risk of developing cervical cancer.  HIV weakens the immune system, making it harder for the body to ward off an HPV infection. A weakened immune system may also cause cervical cancer to develop at a more rapid pace.
• Genetics – A family history of cervical cancer may increase the risk for cervical cancer. It is estimated that if an immediate family member, like a mother or sister, has had cervical cancer, the risk is increased two to three times.
• Multiple Births – Some studies have shown that women who carry seven or more full-term pregnancies are at a higher risk of developing cervical cancer.
• Oral Contraceptives - There is a small cervical cancer risk associated with using birth control pills for longer than five years.  However, many physicians agree that the benefits of oral contraceptives outweigh the risks.
• DES Exposure - Diethylstilbestrol (DES) is a drug used between 1940 and 1971 for women who were at high risk of having a miscarriage.  Female babies born to those who were given DES are at a slight risk of developing a rare form of cervical cancer because of the DES exposure.  Only one out of 1,000 women who were exposed to DES will develop this type of cancer.

Preventing HPV Infection

Since there is no cure for HPV, prevention is the best defense.  A vaccine can now protect young woman from the four types of HPV that cause most cervical cancers and genital warts. The vaccine is recommended for 11 and 12 year-old girls. It is also recommended for girls and women age 13 through 26 who have not yet been vaccinated or completed the vaccine series. Check with your health care provider or go online at http://www.cdc.gov/vaccines/vpd-vac/hpv/default.htm for more information about the vaccine.

Limiting your number of sexual partners can lessen your risk.  However, if you choose to be sexually active, continued use of condoms may lower the risk of HPV.  Condoms may also lower the risk of developing HPV-related diseases, such as genital warts and cervical cancer. But HPV can infect areas that are not covered by a condom, so condoms are not complete protection against HPV.

Testing for Cervical Cancer

Regularly scheduled Pap tests are the best way to detect early changes in your cervix that may indicate pre-cancer.  Women should have their first Pap test within three years after becoming sexually active, or by age 21.  Testing should continue every year until they reach the age of 30, at which time the test can be given every 2-3 years.
If a Pap test indicates abnormal cells are present, the health care provider will suggest follow up tests that may include:

• A repeat of the Pap test to insure the results of the first test were accurately reported
• HPV testing
• Colposcopy, a procedure in which the physician visually checks the genital area with a magnifying instrument called a colposcope
• Biopsy, a surgical procedure that removes a small piece of the tissue in question.  The tissue is then examined in a laboratory.

Remember

The only way to be certain to avoid becoming infected with HPV is to avoid all sexual contact.  However, even if you are infected, your chances of developing cervical cancer are small.  Regular Pap tests are the best way to locate precancerous cells and prevent cancer.