Pap test

Definition

The Pap test checks for cervical cancer. Cells scraped from the opening of the cervix are examined under a microscope. The cervix is the lower part of the uterus (womb) that opens at the top of the vagina.

This test is sometimes called a Pap smear.

Alternative Names

Papanicolaou test; Pap smear; Cervical cancer screening - Pap test; Cervical intraepithelial neoplasia - Pap; CIN - Pap; Precancerous changes of the cervix - Pap; Cervical cancer - Pap; Squamous intraepithelial lesion - Pap; LSIL - Pap; HSIL - Pap; Low-grade Pap; High-grade Pap; Carcinoma in situ - Pap; CIS - Pap; ASCUS - Pap; Atypical glandular cells - Pap; AGUS - Pap; Atypical squamous cells - Pap; HPV - Pap; Human papilloma virus - Pap cervix - Pap; Colposcopy - Pap

How the Test is Performed

You lie on a table and place your feet in stirrups. Your health care provider gently places an instrument called a speculum into the vagina to open it slightly. This allows the provider to see inside the vagina and cervix.

Cells are gently scraped from the cervix area. The sample of cells is sent to a lab for examination.

How to Prepare for the Test

Tell your provider about all the medicines you are taking. Some birth control pills that contain estrogen or progestin may affect test results.

Also tell your provider if you:

• Have had an abnormal Pap test
• Might be pregnant

DO NOT do the following for 24 hours before the test:

• Douche (douching should never be done)
• Have intercourse
• Use tampons

Try not to schedule your Pap test while you have your period (are menstruating). Blood may make the Pap test results less accurate. If you are having unexpected bleeding, do not cancel your exam. Your provider will determine if the Pap test can still be done.

Empty your bladder just before the test.

How the Test will Feel

A Pap test causes little to no discomfort for most women. It can cause some discomfort, similar to menstrual cramps. You may also feel some pressure during the exam.

You may bleed a little bit after the test.

Why the Test is Performed

The Pap test is a screening test for cervical cancer. Most cervical cancers can be detected early if a woman has routine Pap tests.

Screening should start at age 21.

After the first test:

• You should have a Pap test every 3 years to check for cervical cancer.
• If you are over age 30 and you also have HPV testing done, and both the Pap test and HPV test are normal, you can be tested every 5 years. HPV (human papillomavirus) is a virus that causes genital warts and cervical cancer.
• Most women can stop having Pap tests after age 65 to 70 as long as they have had 3 negative tests within the past 10 years.

You may not need to have a Pap test if you have had a total hysterectomy (uterus and cervix removed) and have not had an abnormal Pap test, cervical cancer, or other pelvic cancer. Discuss this with your provider.

Normal Results

A normal result means there are no abnormal cells present. The Pap test is not 100% accurate. Cervical cancer may be missed in a small number of cases. Most of the time, cervical cancer develops very slowly, and follow-up Pap tests should find any changes in time for treatment.

What Abnormal Results Mean

Abnormal results are grouped as follows:

ASCUS or AGUS:

• This result means there are atypical cells, but it is uncertain or unclear what these changes mean.
• The changes may be due to HPV.
• They may be due to inflammation of unknown cause.
• They may be due to lack of estrogen as occurs in menopause.
  
• They may also mean there are changes that may lead to cancer.
• These cells could be precancerous and they could be coming from the outside of the cervix or inside the uterus.

LOW-GRADE DYSPLASIA (LSIL) OR HIGH-GRADE DYSPLASIA (HSIL):

• This means changes that may lead to cancer are present.
• The risk of progression to cervical cancer is greater with HSIL.

CARCINOMA IN SITU (CIS):

• This result most often means the abnormal changes are likely to lead to cervical cancer if not treated

ATYPICAL SQUAMOUS CELLS (ASC):

• Abnormal changes have been found and may be HSIL

ATYPICAL GLANDULAR CELLS (AGC):

• Cell changes that may lead to cancer are seen in the upper part of the cervical canal or inside the uterus.

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

For minor cell changes, providers will recommend another Pap test or repeat HPV testing in 6 to 12 months.

Follow-up testing or treatment may include:

• Colposcopy-directed biopsy -- Colposcopy is a procedure in which the cervix is magnified with a binocular like tool called a colposcope. Small biopsies are often obtained during this procedure to determine the extent of the problem.
• An HPV test to check for the presence of the HPV virus types most likely to cause cancer.
• Cervix cryosurgery.
• Cone biopsy.

References

American College of Obstetricians and Gynecologists. Practice bulletin no. 140: management of abnormal cervical cancer screening test results and cervical cancer precursors. (Reaffirmed 2018) Obstet Gynecol. 2013;122(6):1338-1367. PMID: 24264713 www.ncbi.nlm.nih.gov/pubmed/24264713.

American College of Obstetricians and Gynecologists. Practice bulletin no. 157: cervical cancer screening and prevention. Obstet Gynecol. 2016;127(1):e1-e20. PMID: 26695583 www.ncbi.nlm.nih.gov/pubmed/26695583.

American College of Obstetricians and Gynecologists website. Practice advisory: cervical cancer screening (update). August 29, 2018. www.acog.org/Clinical-Guidance-and-Publications/Practice-Advisories/Practice-Advisory-Cervical-Cancer-Screening-Update. Published August 29, 2018. Reaffirmed November 8, 2019. Accessed March 17, 2020.

Newkirk GR. Pap smear and related techniques for cervical cancer screening. In: Fowler GC, ed. Pfenninger and Fowler's Procedures for Primary Care. 4th ed. Philadelphia, PA: Elsevier; 2020:chap 120.

Salcedo MP, Baker ES, Schmeler KM. Intraepithelial neoplasia of the lower genital tract (cervix, vagina, vulva): etiology, screening, diagnosis, management. In: Lobo RA, Gershenson DM, Lentz GM, Valea FA, eds. Comprehensive Gynecology. 7th ed. Philadelphia, PA: Elsevier; 2017:chap 28.

Saslow D, Solomon D, Lawson HW, et al. American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology screening guidelines for the prevention and early detection of cervical cancer. CA Cancer J Clin. 2012;62(3):147-172. PMID: 22422631 pubmed.ncbi.nlm.nih.gov/22422631.

US Preventive Services Task Force website. Final recommendation statement. Cervical cancer: screening. www.uspreventiveservicestaskforce.org/Page/Document/UpdateSummaryFinal/cervical-cancer-screening2. Updated August 2018. Accessed January 22, 2020.