A Pap smear or Pap test checks for cell changes in the cervix, the lower part of the uterus (or womb) that opens into the vagina. The test can detect some of the earliest signs of cervical cancer as well as infections and abnormal cells that can turn into cancer.
Doctors often perform Pap smears in conjunction with pelvic exams, where a doctor or nurse practitioner looks for redness, swelling, discharge or sores inside and outside the vagina.
During a Pap smear, the doctor inserts an instrument called a speculum into the vagina, opening it to see the cervix. The doctor then uses a special stick or brush to sample cells in and around the cervix.
The cell samples are placed onto a glass slide and delivered to the laboratory for evaluation, which typically takes about three weeks. Most test results are normal, and even abnormal results don't always indicate the development of cancer.
In the event of an abnormal test, the doctor will generally call for additional tests to determine if the cause is cancer or other, lesser problems with the cervix.
Routine Pap tests have led to a decline in the number of cervical cancer cases and deaths. For this reason, women should generally schedule regular Pap smears based on their age:
The human immunodeficiency virus (HIV), which causes AIDS, increases the odds of cervical cancer and other cervical diseases in HIV-positive women. The U.S. Centers for Disease Control and Prevention recommends that women in this group be tested soon after diagnosis and again in six months. If both tests are normal, these women can safely resume annual testing.
Sometimes a test is unclear or shows small changes in the cells of the cervix, in which case a doctor usually repeats the test.
Pap smears can also result in a false positive, meaning the test shows abnormalities that do not exist, which is revealed by further testing.
If an abnormal test suggests there may be more serious changes in the cervix, doctors typically recommend additional procedures, including:
False negatives are another possibility, meaning test results indicate everything is normal when there may be a problem.
A false negative result can delay the discovery and treatment of a cervical problem, making routine Pap smears a valuable procedure to pursue. If a problem is missed on one test, it can be caught during the next, often in time to successfully treat the problem.
Doctors usually suggest scheduling a Pap test 10 to 20 days after the first day of your last period. In order to avoid false results, it’s recommended to avoid douching, using tampons, vaginal deodorants, and vaginal creams, suppositories and similar medications, as well as sexual intercourse for two days before the Pap smear.