Pap Test (Papanicolaou Smear)
What Is It?
The Pap test (Papanicolaou smear) is an examination that is used to detect cervical cancer and precancerous conditions of the cervix. If a Pap test detects a precancerous condition (a change on the surface of the cervix that can lead to cancer), your doctor can treat or remove the abnormal tissue to prevent cervical cancer. If a Pap test detects cervical cancer in its early stages, it may be possible to treat your cancer before it has a chance to spread.
In almost cases, cancer or precancerous changes on the surface of the cervix are caused by a virus infection called human papilloma virus (HPV). Some types of HPV cause genital warts, and some types can cause cancer. Most people who are infected with HPV do not have symptoms, but they can spread the virus to others. HPV is spread through sexual contact with an infected person.
A new test called the HPV DNA test has recently become available. Some laboratories use this test when they process a Pap test sample if the results are uncertain. Previously, cells were inspected under a microscope by hand or with a machine to see if they appeared abnormal. The new HPV DNA test is a chemical test that can detect HPV particles. This chemical test is used in addition to the sample being viewed under a microscope for cell abnormalities.
The HPV DNA test has shown researchers how common this virus really is. Between 20% and 40% of sexually active teenagers test positive for recent HPV exposure, and about 40% of sexually active women between the ages of 20 and 29 have had a positive test result. Because HPV is such a common virus, many sexually active women will have at least one positive Pap test result in their lives.
The Pap test is done during a pelvic examination. Cells are gently scraped from the cervix and are sent to a laboratory for evaluation. The Pap test itself takes only a few moments, but is usually part of a complete gynecological examination that may last between 5 and 20 minutes.
Some doctors now include a close examination of the cervix under blue-white light and through a magnifying glass. This test is called speculoscopy, and is also known as the PapSure test. As of today, most doctors do not use speculoscopy, partly because a large percentage of the abnormalities that this test can identify are later shown to be harmless. It is not clear at this point that the benefit of speculoscopy is worth the additional expense, inconvenience, alarm and complications from follow-up procedures.
What It's Used For
The Pap test is an important screening procedure for cervical cancer. It is used primarily to detect abnormal, precancerous changes that may develop into cervical cancer unless treated. In some cases, the Pap test also will detect cancerous (malignant) cells before cervical cancer becomes visible to the naked eye, and before cancer has spread beyond a localized area.
In general, doctors recommend that a woman start having annual Pap tests when she becomes sexually active or by the age of 21 at the latest. After three negative Pap tests at least one year apart, your doctor may do the test every two to three years, depending on your age and your risk of cervical cancer. More frequent Pap tests may be recommended for women who have a higher risk of cervical cancer because of any of these risk factors:
- A history of sexual intercourse at an early age
- Multiple sex partners
- A history of infection with certain human papillomaviruses
If possible, arrange to schedule your Pap test for the middle of your menstrual cycle (around days 15 to 20). Avoid douching for at least three days before your test date. If you are using contraceptive foam or jelly, it is preferable for you to switch to a different form of birth control or abstain from sex for a few days before your Pap test, because some women have mild irritation of the cervix after using a spermicide.
How It's Done
The Pap test is done by your doctor during a gynecological (pelvic) examination. You will probably be asked to remove all your clothing and be given a robe or gown to wear. Usually, an annual gynecological examination involves a breast exam in addition to a pelvic exam. You will also be given a cloth drape to cover your lower torso. Next, you will be asked to lie on your back on the examination table with your legs spread, feet sitting on rests and your knees bent. Your doctor will insert a lubricated instrument called a speculum into your vagina to hold the vaginal walls open for the Pap test.
After looking at your cervix and vagina to check for any visible problems, your doctor will gently scrape the surface of your cervix with a small spatula to collect a sample of cells from the outside of the cervix. Your doctor also will use a small brush to collect cells from the inside of the cervix. These samples will be suspended in liquid, called ThinPrep, and sent to the laboratory where microscope slides will be prepared and examined. Some doctors will prepare the slides immediately in the clinic.
Once your gynecological exam is finished, you can get dressed and return to your normal daily activities. You may notice a little spotting after the test, so you may choose to use an underwear liner (thin sanitary pad) for a day. After a few days, you should receive a report from your doctor with the Pap test results and recommendations for follow up. You should call your doctor for your Pap test results if you do not receive a report.
The Pap test is a safe and painless procedure.
When To Call a Professional
Call your doctor if you experience discomfort, bleeding for more than a day, or if you have unusual vaginal discharge after your gynecological exam.
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