The Pap Test

What is a Pap test?

The Pap test, sometimes called a Pap smear or cervical cytology screening, is a simple test that can detect abnormal cervical cells. It is not the same as a pelvic exam. The Pap test allows early diagnosis and treatment so that the abnormal cells do not become cancer (see the FAQ HYPERLINK http://www.acog.org/publications/faq/faq163.cfm Cancer of the Cervix). Routine Pap tests help decrease the chance that abnormal cells are missed. If a Pap test misses abnormal cells this time, they may be found on your next Pap test.

How is the Pap test done?

A Pap test is simple and fast. It takes less than a minute to do. With the woman lying on an exam table, a speculum is used to open the vagina. This device gives a clear view of the cervix and upper vagina. A small number of cells are removed from the cervix with a brush or other tool. The cells are put into a liquid and sent to a lab where they are placed on a glass slide. Sometimes, the cell sample is directly placed on a glass slide before it is sent to the lab. At the lab, the sample is examined using a microscope to see if abnormal cells are present. Many labs use a computer to examine the samples.

Who should have a Pap test and how often?

You should start having Pap tests at age 21. How often you should have a Pap test depends on your age and your health history:

Women under 30 should have a Pap test every 2 years.
Women aged 30 and over should have a Pap test every 2 years. After three consecutive normal Pap test results, a woman in this age group can have a Pap test every 3 years if:
she has no history of mild or severe dysplasia.
she is not infected with the human immunodeficiency virus (HIV).
her immune system is not weakened (for example, if she has had an organ transplant).
she was not exposed to diethylstilbestrol (DES) before birth.

When can I stop having Pap tests?

It is not clear when a woman can stop having Pap tests. Some experts recommend that a woman who is aged 65 years or 70 years can stop having Pap tests after three normal results in a row within the past 10 years. However, if you have certain risk factors, you should continue to have routine Pap tests. These risk factors include being sexually active and having had multiple partners or a previous history of abnormal Pap test results.

What happens if a Pap test result is abnormal?

You most likely will have additional testing after an abnormal Pap test result. This testing can be simply a repeat Pap test in 6 months or 12 months, a test for human papillmavirus, or a more detailed examination called a colposcopy (with or without a biopsy). If results of follow-up tests indicate precancerous changes, you may need treatment to remove the abnormal cells.

Is the Pap test result always accurate?

As with any laboratory test, Pap test results are not always accurate. Sometimes the results show abnormal cells when the cells are normal. This is called a false positive result. The Pap test may also fail to detect abnormal cells when they are present. This is called a false negative result. Many factors can cause false results:

The sample may contain too few cells.
There may not be enough abnormal cells to study.
An infection or blood may hide abnormal cells.
Vaginal medications may wash away or dilute abnormal cells.

Your doctor may suggest repeating the Pap test to check the results. A repeat test increases the chance of detecting abnormal cells if they are present.