What is a Pap test?

A Pap test (sometimes called a Pap smear) is a screening test during which a sample of cells is taken from a woman’s cervix and vagina. The test detects changes in the cells of the cervix prior to the development of clinical problems.

The Pap test is your best protection against cervical cancer. A Pap test might help your health care provider detect a problem before you are aware that something is wrong. Early detection is critical to a successful outcome.

How is a Pap test performed?

A Pap test can be done in your doctor’s office during a regular pelvic exam. For the test, a speculum (a device used to widen the vagina) is placed into the vagina, and a sample of cells is taken from the cervix. The cells are placed on a glass slide or in a liquid fixative and sent to a laboratory for analysis.

When should a Pap test be performed?

Several national guidelines recommend:

Low risk patients:
  • Cervical cancer screening should begin at age 21 years regardless of sexual history.
  • For women aged 21 to 29 years, cervical cytology screening is recommended every 3 years.
  • For women 30 years and older, who have had 3 consecutive negative (normal) PAP tests, the recommended screening interval may be continued at every 3 years. The recommended screening interval is every 5 years if HPV (human papillomavirus) testing is performed along with the routine Pap test. Women are candidates for this less frequent Pap testing schedule if they are HPV negative and have no history of CIN 2 or CIN 3 (Cervical Intraepithelial Neoplasia, which are potentially precancerous cells).
  • Women who have HIV, another immunocompromised state (such as those who have had an organ transplant) or DES (diethylstilbestrol) exposure while in the womb should continue with yearly pap tests.
  • Routine Pap testing should be discontinued in women who have had a total hysterectomy for benign conditions, assuming they have no history of high-grade CIN.
  • Cervical cancer screening can be discontinued at age 65 in women who have 3 or more consecutive negative cytology test results and no abnormal test results in the past 10 years.

What happens if the Pap test results are abnormal?

An abnormal Pap test may not mean that cancer cells were found during the examination. There are many causes for abnormal Pap test results.

Your health care provider will evaluate the results to determine if you should have:

  • A repeat Pap test
  • A colposcopy
  • An HPV test
  • A combination of the above

Based on the results of these procedures and tests, you might need additional treatment.

Why might a repeat Pap test be necessary?

A repeat Pap test might be necessary if you had an infection at the time of the Pap test or if there were not enough cells collected during the Pap test. Since decreased levels of estrogen can lead to vaginal atrophy (gradual decline in size and function) and also influence Pap test results, menopausal women might need to take estrogen before the repeat Pap test.

If the results of the repeat Pap test are still abnormal, your health care provider might recommend that you have a colposcopy to further evaluate the problem.

What is colposcopy?

Colposcopy is a closer examination of the cervix and the walls of the vagina. During the examination, a speculum is inserted into the vagina (as done in a Pap test). A doctor looks through a magnifying instrument called a colposcope to detect cervical problems that cannot be seen by the eye alone. Acetic acid (vinegar) is often used on the cervix to help visualize abnormal cells. During the colposcopy, the colposcope remains outside the vagina. Biopsies (tissue samples) of the abnormal cervical area might be taken. Discomfort during this procedure is minimal.

Colposcopy is not always necessary immediately after an abnormal Pap test. Your health care provider will follow national guideline recommendations to determine best follow up depending on your type of abnormal Pap result.

What type of follow-up is recommended for an abnormal Pap test?

Based on new follow-up guidelines for minimally abnormal Pap tests (ASCUS-atypical squamous cells of undetermined significance), colposcopy is recommended as a follow-up option only when the HPV test is positive. Colposcopy is not recommended as the first option for evaluation unless the Pap test results indicate a definite and more severe abnormality.

What is the HPV test?

The HPV (human papillomavirus) test detects the presence of a virus that can cause abnormal cervical cells or cervical cancer. HPV infection has been shown to be the primary cause of almost all cancerous and precancerous conditions of the cervix. A sample for HPV testing is collected with the Pap smear sample in women over the age of 30. Women younger than age 30 should not have HPV testing done routinely, as many HPV infections in this age group are temporary, and can lead to unnecessary tests and procedures. However, in women aged 21 to 29, HPV testing is often performed on the Pap smear specimen after an abnormality has been detected, without requiring a second visit (to help understand how to address the abnormal Pap result).

What do the results of the HPV test indicate?

The HPV test results can accurately distinguish women who are at higher risk to have cervical abnormalities from those who do not. When compared to a Pap follow-up only, this test reduces the risk of delayed detection of high-grade disease or cervical cancer. In addition, the HPV test is a less expensive alternative to colposcopy. Colposcopy is often unnecessary when performed as the first follow-up option for minimal abnormalities indicated by a Pap test if they are negative for HPV.

What follow-up is needed if the Pap shows atypical squamous cells of undetermined significance (ASCUS)?

Pap results showing ASCUS cells are one of the most common abnormalities seen. If the HPV test results are negative, and a patient has a Pap abnormality showing ASCUS cells, a follow-up Pap test is usually recommended in 3 years. If the hybrid capture test results are positive, with ASCUS, a colposcopy is recommended. Recommendations for subsequent repeat Pap tests will be made by your health care provider after the colposcopy.


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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 1/27/2015...#4267