Pap smear

Definition

A Pap smear is an examination under the microscope of cells scraped from the cervix.

Alternative Names

Papanicolaou test

How the test is performed

The Pap smear is done as part of a gynecological exam. You will lie on a table and place your feet in stirrups to position your pelvis for examination. The health care provider will insert an instrument (speculum) into your vagina and open it slightly to see inside the vaginal canal.

The health care provider will take a sample of cells from outside and inside the canal of the cervix by gently scraping the outside of the cervix with a wooden or plastic spatula, then inserting a small brush that looks like a pipe cleaner into the canal.

The cells are placed on a glass slide, or put in a bottle containing a preservative, and then sent to the lab for examination.

How to prepare for the test

Tell your health care provider if you:

• Are taking any medications or birth control pills
• Have had an abnormal Pap smear
• Might be pregnant

Within 24 hours of the test, avoid:

• Douching
• Having intercourse
• Taking a tub bath
• Using tampons

Avoid scheduling your Pap smear while you have your period (are menstruating), because blood and cells from the uterus may affect the accuracy of the Pap smear. Empty your bladder just before the test.

How the test will feel

You may have some discomfort, similar to menstrual cramps, and a feeling of pressure during the procedure. You may bleed a little bit after the test.

Why the test is performed

The Pap smear can detect cancerous or precancerous conditions of the cervix. It should be done on a regular basis (see physical exam frequency for how often Pap smears should be performed).

Normal Values

A normal value is negative, meaning there are no abnormal cells present.

Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

What abnormal results mean

The Pap smear is a screening test. Abnormal values are based on the test results. The current system divides the results into three main areas:

• ASCUS or AGUS (atypical cells of uncertain significance)
• LSIL (low-grade dysplasia) or HSIL (high-grade dysplasia)
• Possibly cancerous (malignant)

When a Pap smear shows abnormalities, further testing or follow-up is needed. The next step depends on the results of the Pap smear, your previous history of Pap smears, and risk factors you may have for cervical cancer.

• If the Pap smear shows minor cell changes or abnormalities, a colposcopy-directed biopsy probably will NOT be done right away unless there is a reason to believe you may be in a high-risk category.
• With an ASCUS result, an HPV test is done to check for the presence of the HPV virus types most likely to cause cancer. If the HPV test is negative, then colposcopy will not be needed.
• For minor cell changes, doctors usually recommend having a repeat Pap smear in 6 months. With a negative HPV test result, it's acceptable to have the repeat Pap done in 1 year.

What the risks are

There are no risks involved.

Special considerations

The following drugs may affect Pap smears:

• Colchicine
• Compounds in cigarettes
• Estrogen
• Podophyllin
• Progestins
• Silver nitrate

References

ACOG Committee on Practice Bulletins. ACOG Practice Bulletin Number 45, August 2003: Cervical Cytology. Obstetrics & Gynecology. 2003;102(2):417-427.

Smith RA, Cokkinides V, Eyre HJ. American Cancer Society guidelines for the early detection of cancer, 2006. CA Cancer J Clin. 2006;56:11-25.

Wright TC Jr, Massad LS, Dunton CJ et al. 2006 American Society for Colposcopy and Cervical Pathology-sponsored Consensus Conference. 2006 consensus guidelines for the management of women with abnormal cervical cancer screening tests. Am J Obstet Gynecol. 2007;197(4):346-55.