Pap Smear

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Pap smear facts

  • A Pap smear is a simple, quick, and essentially painless screening test.
  • Cells collected from a woman's cervix are spread on a microscope slide for examination.
  • The cells are evaluated for abnormalities, specifically for pre- cancerous and cancerous changes.
  • Pap smears are recommended for all women starting at age 21 years or within 3 years of becoming sexually active, whichever comes first.
  • Most women over age 30 who have had reliable Pap screening with persistently normal results can be screened less often than yearly.
  • Pap smears should not be performed in women who have had a total hysterectomy for benign conditions and had prior normal Pap smears.
  • The Pap smear is read (analyzed) according to a uniform standardized system known as the Bethesda System.
  • A recording of the woman's menstruation status and whether and when she had abnormal Pap smears previously, is essential to the reader of the current Pap smear.
  • Screening guidelines recommend that most women over 65-70 years old who have had regular Pap screening with negative results can stop having Pap tests, because abnormal Pap smears are very unusual in this setting.
  • Up to 80% of women diagnosed with invasive cancer of the cervix have not had a Pap smear in the past 5 years.
  • Cancer of the cervix is a preventable disease.

What is a Pap smear?

A Pap smear (also known as the Pap test) is a medical procedure in which a sample of cells from a woman's cervix (the end of the uterus that extends into the vagina) is collected and spread (smeared) on a microscope slide. The cells are examined under a microscope in order to look for pre-malignant (before-cancer) or malignant (cancer) changes.

A Pap smear is a simple, quick, and relatively painless screening test. Its specificity, which means its ability to avoid classifying a normal smear as abnormal (a "false positive" result), while very good, is not perfect. The sensitivity of a Pap smear, which means its ability to detect every single abnormality, while good, is also not perfect, and some "false negative" results (in which abnormalities are present but not detected by the test) will occur. Thus, a few women develop cervical cancer despite having regular Pap screening.

In the vast majority of cases, a Pap test does identify minor cellular abnormalities before they have had a chance to become malignant and at a point when the condition is most easily treatable. The Pap smear is not intended to detect other forms of cancer such as those of the ovary, vagina, or uterus. Cancer of these organs may be discovered during the course of the gynecologic (pelvic) exam, which usually is done at the same time as the Pap smear.

Who should have a Pap smear?

Reader Stories

Pregnancy does not prevent a woman from having a Pap smear. Pap smears can be safely done during pregnancy.

Pap smear testing is not indicated for women who have had a hysterectomy (with removal of the cervix) for benign conditions. Women who have had a hysterectomy in which the cervix is not removed, called subtotal hysterectomy, should continue screening following the same guidelines as women who have not had a hysterectomy.

Medically Reviewed by a Doctor on 5/21/2015

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Pap Smear - Results Question: What was the outcome of your abnormal Pap smear results?
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