Human Papillomavirus (HPV) Test
- Every 5 years with a Pap smear (preferred) or HPV molecular test alone every 5 years (alternative strategy) when you are a woman aged 30 to 65 with average risk
- You may be screened at a younger age and more frequently if you have risk factors, such as a weakened immune system or personal history of precancerous lesions
- If you are a woman aged 21 to 29 and have an abnormal Pap smear result
A sample of cells is taken from the cervical area during a pelvic exam using a swab or small brush. The sample is then placed into a bottle containing a special liquid preservative. The same sample of cells can be used for both the Pap smear and the HPV test.
It is typically recommended that you refrain from having sex, douching, or using vaginal products such as creams, deodorants, or medications for 24 hours before the test. Follow any instructions you are given. Reschedule the test if you are having your period (menstruating). You may be asked to empty your bladder before the examination. The American Cancer Society has details about how to prepare for the test when it is done at the same time as a Pap smear.
Human papillomavirus (HPV) is a group of more than 150 related viruses. Some types of HPV are considered high risk because they can cause cancer. HPV testing detects the genetic material (DNA or messenger RNA) of high-risk HPV (hrHPV), primarily to screen for cervical cancer or to determine whether you may be at risk of cervical cancer.
Some types of HPV can cause skin warts, while other types can cause genital warts (also called condylomata). Genital HPV infection is one of the most common sexually transmitted diseases (i.e., spread through oral, anal, or genital sex). According to the U.S. Centers for Disease Control and Prevention, about 79 million Americans are infected with HPV and over 14 million become newly infected each year.
- Low-risk HPV—some HPV strains cause genital warts but rarely cause cancer. HPV 6 and HPV 11 cause 90% of all genital warts but are considered "low risk" because they rarely lead to cancer. These low-risk types can be diagnosed through visual inspection and, therefore, do not require testing.
- High-risk HPV—there are 14 high-risk types of HPV that can lead to cancer (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and 68). Two HPV types,16 and 18, cause 80% of all cervical cancers. These high-risk types can be detected with an HPV test.
Many HPV infections resolve without treatment—the body is able to clear the infection. However, infections with high-risk HPV types that do not go away can lead to cervical cancer. Almost all cervical cancers are caused by persistent infections with high-risk HPV. Each year, nearly 12,000 women in the U.S. develop cervical cancer and about 4,000 are expected to die from it.
In addition, some studies have also shown that persistent oral infections with high-risk types of HPV are strongly associated with oral cancers, including cancer of the mouth and throat (oropharyngeal cancer). Anal cancer has also been linked to HPV types 16 and 18. These types are also linked to other cancers, such as those of the vagina and penis.
How is it used?
The HPV test is primarily used to screen for cervical cancer and/or determine whether you may be at increased risk of cervical cancer if you are a woman between the ages of 30 and 65. The test determines whether your cervical cells are infected with a high-risk type of human papillomavirus (hrHPV). Such an infection, if long-lasting, can cause changes in cervical cells that could lead to cervical cancer.
Because HPV infections are relatively common in women younger than 25 and often go away without treatment or complications, HPV screening is not recommended in this age group. However, HPV testing may be used as a follow-up test in women between the ages of 21 and 29 years who have abnormal results on a Pap smear known as "atypical squamous cells of undetermined significance" (AS-CUS). Results may be used to determine the need for colposcopy, a procedure that allows a healthcare practitioner to visually inspect the vagina and cervix under magnification for any abnormal areas and to collect samples for a biopsy and/or treat as necessary.
When is it ordered?
Several health organizations have recommendations on when to get screened for cervical cancer. HPV testing may be ordered as part of screening when you are at average risk of cervical cancer and between the ages of 30 and 65. The following is a summary of screening recommendations for average risk women:
Screening Strategy Timing Pros Cons Co-testing with a Pap smear (Pap test) and HPV test (preferred) Every 5 years Will likely detect more precancers and cancers; done less frequently than Pap smears alone More false positives than Pap smear alone, leading to unnecessary anxiety and follow up Pap smears alone (acceptable) Every 3 years Fewer false positives Not as sensitive as co-testing (may miss some precancers and cancers); Done more often HPV tests alone (alternative) Every 5 years Done less frequently than Pap smears alone Finds HPV infections that may not cause problems; misses uncommon cancers that are not caused by HPV
You should have a discussion with your healthcare provider about the pros and cons of all three screening strategies so you can decide which approach is best for you.
Screening at a younger age and more frequent screening is advised if you have risk factors such as:
- A previous diagnosis of a high-grade precancerous cervical lesion or cervical cancer
- HIV infection
- A weakened immune system
- Exposure to DES (diethylstilbestrol) before birth
HPV testing also may be performed when you are between 21 and 29 years of age and you have abnormal results on a Pap smear.
What does the test result mean?
HPV test and Pap smear results go hand-in-hand when determining a woman's risk for cervical cancer. Results from an HPV test and Pap smear can help determine whether cervical cells are infected with a high-risk type of HPV and identify abnormal changes in cervical cells.
HPV results are typically reported as negative or positive. Pap smear results are typically provided in a detailed report with an interpretation of results. (See the Pap Smear article for details.)
The following chart summarizes the meaning of some common co-testing results and includes the American Cancer Society (ACS), American Society for Colposcopy and Cervical Pathology (ASCCP), and American Society for Clinical Pathology (ASCP) recommendations for follow up. Remember, co-testing is currently recommended for women aged 30 to 65 years.
Co-testing Results What Results Might Mean Recommended Follow Up HPV test negative, Pap smear normal Cervical cancer risk is low at the present time. Repeat co-testing in 5 years (or Pap test alone in 3 years) HPV test positive, Pap smear normal Cervical cells are infected with a high-risk type of HPV, but no abnormalities found in cervical cells. Option 1: Repeat co-testing in 12 months
Option 2: Test for HPV-16 and HPV-18
- Positive: colposcopy recommended to examine the cervix for abnormal areas, to take samples for biopsy, and/or treat as indicated
- Negative: repeat co-testing in 12 months
HPV test negative, Pap smear result unclear (ASCUS) No HPV infection; changes in cervical cells may be the result of infection, inflammation, or hormonal changes and are likely to clear up without treatment. Repeat co-testing in 3 years HPV test positive, Pap smear result unclear (ASCUS) Cervical cells are infected with a high-risk type of HPV. The infection is the likely cause of abnormalities in your cervical cells. Colposcopy recommended HPV test negative, Pap smear abnormal [low- or high-grade lesion (LSIL, HSIL)] No HPV infection; cause of abnormal cervical cells unknown Option 1: Repeat co-testing in 12 months
Option 2: Colposcopy recommended
HPV test positive, Pap smear abnormal [low- or high-grade lesion (LSIL, HSIL)] Cervical cells are infected with a high-risk type of HPV, which is the likely cause of abnormal cell growth. Colposcopy recommended
If a Pap smear is performed without an HPV test, the presence of abnormal cervical cells indicates the need to perform an HPV test to determine whether HPV infection is the cause of the cellular changes.
Is there anything else I should know?
Most people who become infected with high-risk types of HPV never develop precancerous changes or cancer.
Being infected with HPV does not necessarily mean that your partner is having sex outside your relationship. The HPV virus can hide in cervical cells for many years; so if either of you has ever had sex with another partner, you can pass the infection to your current partner.
Although very rare, a pregnant woman may pass HPV to her baby during vaginal delivery, resulting in warts in the throat or voice box (laryngeal papillomatosis or recurrent respiratory papillomatosis, RRP).
Being infected with HPV will not make it difficult for you to get pregnant or carry a pregnancy to term. However, some methods of treating precancerous growths resulting from HPV infection can make it more difficult to get pregnant or have an uncomplicated delivery.
How is HPV treated?
There is no treatment for the virus itself, but the body's immune system is usually able to clear the infection within a few years. There are treatments, however, for the conditions the virus causes. Precancerous growths on the cervix can be treated in a variety of ways, from cryosurgery that freezes and destroys abnormal cells, to surgical removal of abnormal tissue. Catching cervical changes early is the key to avoiding cervical cancer, which is more difficult to treat.
Genital warts can be removed using chemicals, by freezing them or burning them off electrically, or via surgery or lasers. For most people, this treatment will clear the warts. If warts return repeatedly, a healthcare practitioner may try injecting them with the drug interferon. Untreated genital warts can disappear on their own, stay the same, or grow in size and number and cluster in large masses.
How can HPV be prevented?
Vaccination may prevent most cancers and other health problems caused by HPV.
The American Academy of Pediatrics (AAP) and the U.S. Centers for Disease Control and Prevention (CDC) recommend that both girls and boys receive the HPV vaccine series when they are 11 to 12 years old. (Vaccination can be started as early as 9 years of age.) The vaccine is also recommended for:
- Males up to 21 years of age and women up to 26 years of age who did not receive or complete the vaccination series when they were younger
- Young men who have sex with men through age 26 and transgender people through age 26
- People aged 22-26 who have weakened their immune systems, such as those who are HIV-positive, have had an organ transplant, or have used steroids for a long time
In October 2018, the U.S. Food and Drug Administration (FDA) approved expanded use of the HPV vaccine to include women and men aged 27 through 45 years, but this use is not yet included in formal recommendations. If you fall into this group, you may want to talk to your healthcare practitioner about receiving the vaccine.
The only vaccine currently used in the United States protects against nine HPV types (HPV 9-valent vaccine), including seven types that can cause cancer. Of the 32,500 cancers that HPV has caused every year, about 30,000 (90%) are caused by strains that could have been prevented by the 9-valent HPV vaccine.
The most common HPV-related cancer in women is cervical cancer (49%). Examples of others include cancers of the anus (18%), vulva (16%) and back of the throat (oropharynx) (11%). In men, the most common is cancer of the back of the throat (81%). Examples of others include anus (12%) and penis (7%).
The vaccine may be given in a series of 2 or 3 shots. For more information about dosing schedules, see the CDC website. Women who have been vaccinated against HPV should still undergo regular cervical cancer screening using one of the three strategies mentioned earlier.
The FDA and the CDC state that the HPV vaccine is considered safe but is most effective if given before an initial exposure to the virus. The American Academy of Pediatrics and the CDC both recommend that young people who are sexually active still receive the vaccination, as those already infected with one type of HPV infection may benefit from the protection against other types included in the vaccine.
Safer sexual practices
Although monogamy (having sex with only one partner) will not keep you from becoming infected with HPV if either of you has ever had sex with someone who was infected, limiting your number of sex partners will reduce your risk of infection.
Using condoms may reduce the risk of spreading HPV, but only the skin and mucus membranes that are covered by or comes in contact with the condom is protected from HPV. The virus can infect any uncovered skin or mucus membranes on the genitals, groin, thighs, anus, and rectum and possibly in the mouth.
Are men screened for HPV infection?
Men are not routinely screened for HPV infection unless they fall into a category at high risk for cancer, such as those with compromised immune systems or men who have sex with men. Currently, there are no molecular tests approved by the Food and Drug Administration (FDA) to detect HPV in men. However, some specialty labs have validated molecular HPV tests for analyzing anal swabs from men. Additionally, men at high risk may be tested using a Pap test in which cells from the anus are examined under a microscope for abnormalities. As in cervical samples, positive results need to be followed up by the healthcare practitioner with further testing, including a more thorough exam and possible biopsy.
I'm a woman who has had the HPV vaccine. Do I need cervical cancer screening?
Besides HPV, what are other risk factors for cervical cancer in women?
According to the National Cancer Institute, certain factors can further increase your risk of developing cervical cancer after you have become infected with HPV. These include having multiple (3 or more) full-term pregnancies, long-term oral contraceptive (birth control pill) use, and cigarette smoking.
Increased risk for cervical cancer is also associated with:
- Having a compromised immune system (e.g., HIV infection, after an organ transplant)
- Being overweight
- A diet lacking in fruits and vegetables
- A history of exposure to DES (a drug given to some women between 1940 and 1971 to prevent miscarriage) before birth
- A family history of cervical cancer
- A history of chlamydia infection