Pap Smear: What Is, How it Works & Results

The pap smear, short for the Papanicolau smear, is indicated for women as soon as they become sexually active. This test detects cervical changes and illnesses, like inflammation, HPV and cancer. Although the exam is usually recommended for women who are sexually active, it can also be done to women who are not sexually active after the age of 21.

This quick test does not require a lot of preparation and it is completed by a licensed health care professional, like a doctor, gynecologist, nurse practitioner or registered nurse.

A pap smear is not painful, however you may feel some discomfort or pressure inside the vagina when the cervix is scraped for specimen collection. The specimen is then sent to the laboratory for analysis, and result are usually received within 10 days.

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What it tests

Pap smears look for cellular changes in the uterus and it can detect:

  • Vaginal infections like trichomoniasis, candidiasis (yeast infection) or bacterial vaginosis from gardnerella vaginalis
  • Sexually transmitted infections, like chlamydia, gonnorheia, syphillis, or HPV
  • Cervical cancer
  • Cervical health status, like the presence of nabothian cysts (which are small fluid-filled masses that grow due to accumulated mucus from cervical glands)

Pap smears can be done on women over the age of 21 who are not sexually active if indicated by the doctor. In this case, the test is done to assess for abnormalities (e.g. not just part of a routine exam).

How the exam is done

The pap smear is easy, fast and completed in a health care setting, like your doctor’s office or a women’s health clinic. Women are often given instructions for preparation, like avoiding booking the pap smear appointment when you are on your period, and to avoid sex, vaginal douching and any vaginal products for at least 48 hours before the test.

During, the exam, the woman will be instructed to lie on her back on the exam bed and to place her heels in stirrups. The health care provider will place a speculum with a light in the vagina to visually inspect the cervix. Then, the health care provider will use a spatula-like or brush-like instrument to collect cervical cells for analysis at the laboratory. These cells will either be placed on slidesin a small container of solution. The microbiology department of the laboratory will analyze the cells through a microscope to identify any changes or to detect the presence of microorganisms.

The test itself is not painful, but it is common to feel some discomfort or pressure in the uterus during the exam. Any discomfort will usually resolve as soon as the speculum is removed and the exam is completed.

How to prepare for the test

Preparation for the pap smear is straight-forward. It typically involves the avoidance of specific things 2 days prior to the exam, like sexual intercourse (even with a condom), vaginal douching and medication use or vaginal contraceptives.

Also, the woman should not be on her period, as the presence of blood may affect the final results. 

When to book a pap smear

The pap smear is recommended for women who are sexually active, up until the age of 65. Women between 25 and 65 are usually most targeted to complete this test. Pap tests should be completed yearly, however if you've had a negative result for two consecutive years, then the exam can be completed every 3 years. Cervical cell changes are very slow, and therefore it is safe to complete your pap smears with less frequency if you have a history or normal results.

In women over the age of 64, two pap smears should be completed within 1 to 3 years of eacg other. With women who have positive results (ie. lesions that could indicate cervical cancer), pap tests are done every 6 months. Cervical cancer is often caused by the human papilloma virus (HPV), which should be identified and monitored to prevent the development of cancer.

Pap smears in pregnancy

Pap smears can also be done during pregnancy, usually up until the fourth month of gestation. It is usually done at the first prenatal appointment if the woman is not up-to-date. The test is safe for the baby, as it does not reach the inside of the uterus nor the fetus.

What the results mean

Results of pap smears are communicated by the laboratory and will depend on the characteristics observed through the microscope. Results are usually reported using the Bethesda system, are classified as:

  • Unsatisfactory: which means there were insufficient cells collected for analysis
  • Normal: Which means that the cervical cells appear to be within normal limits and no bacteria or viruses were detected
  • Abnormal: Which means that there may be changes to cervical cells which could be benign or malignant and/or bacteria or viruses were detected

Depending on the result, your health care provider will inform you if further exams or treatment is required. If HPV infection or cell abnormalities are detected, the pap smear is usually repeated in 6 months. If cancer is suspected, then a colposcopy is usually ordered. A colposcopy is a more extensive vaginal exam that involves inspection of the vulva, vagina and uterus.