Pap smear test to help prevent cervical cancer or find it early. The cervix is the lower, narrow end of the uterus that opens into the vagina. During a Pap smear, a health care provider collects cells from the cervix and sends them to a lab.
At the lab, the cells are checked under a microscope for cancer or for signs that they may become cancer. Cells that may become cancer are called precancers. Finding and treating precancers can help prevent cervical cancer. The Pap smear is also a reliable way to find cancer early when it’s easier to treat.
Other names for a Pap smear: Pap test, cervical cytology, Papanicolaou test, Pap smear test, vaginal smear technique.
What is the cervix?
The cervix is the lower part of your uterus that connects to your vaginal canal. Sperm travels through the vaginal canal and cervix to your uterus to fertilize eggs. During pregnancy, the cervix closes to keep the baby in your womb (uterus). The cervix opens during childbirth. When you aren’t pregnant, your cervix makes mucus to keep infection-causing bacteria out of your body.
What can a Pap smear detect?
Healthcare providers perform Pap smears as part of a pelvic exam. The test checks for:
- Cervical cancer.
- Potentially precancerous cells in the cervix (cervical intraepithelial neoplasia).
- Human papillomavirus (HPV), a common sexually transmitted disease (STD) that increases the risk of cervical cancer.
How often do I need a Pap smear?
In general, if you’re between age 21 and 65, you should have regular Pap smears:
- If you’re between ages 21 and 29 and your last Pap test result was normal, your provider may say you can wait three years until your next test.
- If you’re between ages 30 and 65 and your last Pap smear result was normal:
- Your provider may say you can wait three years until your next test.
- If you also had a normal HPV test result, your provider may say that you can wait five years until your next test.
- If you’re over age 65, your provider may tell you that you don’t need Pap smears anymore if you:
- Have had normal Pap smears for several years.
- Have had surgery to remove your uterus and cervix because you had a condition that was not cancer, such as fibroids.
If you have a higher risk for developing cervical cancer, your provider may recommend screening more often or after age 65. You may have a higher risk if you:
- Had an abnormal Pap smear in the past
- Have HIV
- Have a weakened immune system
- Were exposed to a drug called DES (Diethylstilbestrol) before you were born. Between the years 1940–1971, DES was prescribed during pregnancy to prevent miscarriages. It was later linked to an increased risk of certain cancers in the female children exposed to it during the pregnancy.
If you’re under age 21, cervical cancer screening is not recommended. Your risk of cervical cancer is very low. Also, any changes in cervical cells are likely to go away on their own.
If you are unsure whether you need a Pap smear, talk with your provider.
How should I prepare for a Pap smear?
Some things that you do in the days before a Pap smear can affect test results. For the most accurate results, you should:
- Not have vaginal sex for two days before your exam.
- Not use tampons, vaginal creams or medicines, birth control foams or jellies, lubricants or douches for at least two days before the test.
- Schedule the appointment at least five days after your period ends.
How is a Pap smear done?
During the procedure, your healthcare provider:
- Inserts a speculum into the vagina. You may feel a bit of pressure. This metal or plastic tool holds your vagina open so your provider can see your cervix.
- Uses a small brush or spatula to gently scrape cells from your cervix (a biopsy).
It isn’t painful, but you’ll probably feel some discomfort.
How often should a Pap smear be repeated?
Doctors generally recommend repeating Pap testing every three years for women ages 21 to 65.
Women age 30 and older can consider Pap testing every five years if the procedure is combined with testing for HPV. Or they might consider HPV testing instead of the Pap test.
If you have certain risk factors, your doctor may recommend more-frequent Pap smears, regardless of your age. These risk factors include:
- A diagnosis of cervical cancer or a Pap smear that showed precancerous cells
- Exposure to diethylstilbestrol (DES) before birth
- HIV infection
- Weakened immune system due to organ transplant, chemotherapy or chronic corticosteroid use
- A history of smoking
You and your doctor can discuss the benefits and risks of Pap smears and decide what’s best for you based on your risk factors.
What happens during a Pap smear?
During a Pap smear you will lie on an exam table. Your provider will use a plastic or metal instrument called a speculum to widen the vagina, so the cervix can be seen. Your provider will then use a small, soft brush or swab to collect cells from the cervix. The cell sample is sent to a lab for testing.
A Pap smear is often done as part of a pelvic exam. During a pelvic exam, your provider examines your uterus, ovaries, and genital area. But a pelvic exam doesn’t always include a Pap smear. So, when you have a pelvic exam, ask your provider whether you’ll have a Pap smear, too.
Are there any risks to getting a Pap smear?
Pap smears are very safe and highly reliable. You may experience light spotting (vaginal bleeding) after the test, but you shouldn’t have cramps or pain. There is a small risk of false-negative or incorrect results, but this is rare.
A false-negative result doesn’t mean that a mistake was made. Factors that can cause a false-negative result include:
- An inadequate collection of cells
- A small number of abnormal cells
- Blood or inflammatory cells obscuring the abnormal cells
Although it’s possible for abnormal cells to go undetected, time is on your side. Cervical cancer takes several years to develop. And if one test doesn’t detect the abnormal cells, the next test most likely will.
How you prepare
To ensure that your Pap smear is most effective, follow these tips prior to your test:
- Avoid intercourse, douching, or using any vaginal medicines or spermicidal foams, creams or jellies for two days before having a Pap smear, as these may wash away or obscure abnormal cells.
- Try not to schedule a Pap smear during your menstrual period. It’s best to avoid this time of your cycle, if possible.
What do the results mean?
A Pap smear test has three possible results:
- Normal Pap smear or “negative” result. No abnormal changes were found in the cells of your cervix. Your provider may tell you that you can wait three years for your next test. If you also had a normal HPV test result, you may be able to wait five years for your next test, depending on your age and medical history.
- Unclear or unsatisfactory results. The lab sample may not have had enough cells, or the cells may have been clumped together or hidden by mucus. Your provider will usually ask you to come in for another test in 2 to 4 months.
- Abnormal Pap smear or “positive” result. Abnormal changes were found in your cervical cells. Most of the time, abnormal results do not mean you have cervical cancer. Minor changes in the cells usually go back to normal on their own. But your provider may recommend a follow-up test to check. More serious cell changes may turn into cancer if they are not removed. Finding and treating these cells early can help prevent cancer from developing.
If only normal cervical cells were discovered during your Pap smear, you’re said to have a negative result. You won’t need any further treatment or testing until you’re due for your next Pap smear and pelvic exam.
If abnormal or unusual cells were discovered during your Pap smear, you’re said to have a positive result. A positive result doesn’t mean you have cervical cancer. What a positive result means depends on the type of cells discovered in your test.
Here are some terms your doctor might use and what your next course of action might be:
- Atypical squamous cells of undetermined significance (ASCUS). Squamous cells are thin and flat and grow on the surface of a healthy cervix. In the case of ASCUS, the Pap smear reveals slightly abnormal squamous cells, but the changes don’t clearly suggest that precancerous cells are present. With the liquid-based test, your doctor can reanalyze the sample to check for the presence of viruses known to promote the development of cancer, such as some types of human papillomavirus (HPV). If no high-risk viruses are present, the abnormal cells found as a result of the test aren’t of great concern. If worrisome viruses are present, you’ll need further testing.
- Squamous intraepithelial lesion. This term is used to indicate that the cells collected from the Pap smear may be precancerous. If the changes are low grade, it means the size, shape and other characteristics of the cells suggest that if a precancerous lesion is present, it’s likely to be years away from becoming a cancer. If the changes are high grade, there’s a greater chance that the lesion may develop into cancer much sooner. Additional diagnostic testing is necessary.
- Atypical glandular cells. Glandular cells produce mucus and grow in the opening of your cervix and within your uterus. Atypical glandular cells may appear to be slightly abnormal, but it’s unclear whether they’re cancerous. Further testing is needed to determine the source of the abnormal cells and their significance.
- Squamous cell cancer or adenocarcinoma cells. This result means the cells collected for the Pap smear appear so abnormal that the pathologist is almost certain a cancer is present. “Squamous cell cancer” refers to cancers arising in the flat surface cells of the vagina or cervix. “Adenocarcinoma” refers to cancers arising in glandular cells. If such cells are found, your doctor will recommend prompt evaluation.
If your Pap smear is abnormal, your doctor may perform a procedure called colposcopy using a special magnifying instrument (colposcope) to examine the tissues of the cervix, vagina and vulva.
Is there anything else I need to know about a Pap smear?
Thousands of women in the U.S. die from cervical cancer every year. A Pap smear, along with an HPV test, is one of the most effective ways to prevent cervical cancer.