What is a Pap Smear?
A Pap smear is a test to screen for cervical cancer. If cervical cancer is found and treated early, there is a better chance it can be cured. This type of cancer starts in the cells of the cervix. Your cervix is the lower part of your uterus, the place where a developing baby grows during pregnancy. The cervix opens into your vagina.
Cervical cancer develops slowly over time. Before cancer appears in the cervix, the cells of the cervix go through changes in which abnormal cells begin to appear in the cervical tissue. This is called dysplasia. Over time, if not destroyed or removed, the abnormal cells may become cancer cells. They can grow and spread into other parts of the cervix and the areas around it.
During a Pap smear, your health care provider collects cells from your cervix and sends them to a lab. There, the cells are checked under a microscope for cancer or signs that they are abnormal and may become cancer. Cells that may become cancer are called precancerous cells. Finding and treating precancerous cells can help prevent cervical cancer.
The Pap smear is also a reliable way to find cancer early, when it's easier to treat. A pap smear may also find certain infections or inflammation.
Other names for a Pap smear: Pap test, cervical cytology, Papanicolaou test, Pap smear test, vaginal smear technique
What is it used for?
A Pap smear looks for abnormal changes in cervical cells before they become cancer. Sometimes, the cells collected during a Pap smear are also checked for HPV (human papillomaviruses). HPV is the name of a group of related viruses, some of which can spread through sexual contact. HPV can cause cell changes that may lead to cancer, including in the cervix. Long-lasting infections with high-risk types of HPV cause almost all cervical cancers. So if you have a cervix and are infected with these types of HPV, you have a higher risk of getting cervical cancer.
Pap smears and HPV tests are cervical cancer screeningtests that look for cancer before you have any symptoms. Cervical cancer screening can reduce your risk of getting cervical cancer or dying from the disease. Ask your provider which test is right for you or if you should have both a Pap smear and an HPV test.
How often do I need a Pap smear?
Your age and health history will help determine how often you should have a Pap smear. If you have a cervix, it's recommended that you have your first Pap smear at age 21.
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 Pap test.
- At age 25, you should begin screening with an HPV test and have them every five years through age 65.
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 Pap smear.
- 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 had an HPV test and a Pap smear, called co-testing, and had normal results for both, your provider may say that you can wait five years until your next test.
If you're over age 65, talk with your provider about whether you still need Pap smears. If you've had regular screenings with normal results, they may tell you that you don't need Pap smears anymore.
You don't need cervical cancer screening if you had a total hysterectomy(surgery to remove your uterus and cervix) because of a condition that was not cancer. But if your hysterectomy was related to cervical cancer or precancer, ask your provider whether you need screening.
If you are at higher risk of developing cervical cancer, your provider may recommend screening more often. You may be at higher risk if you:
- Had an abnormal HPV test, Pap smear, or cervical biopsyin the recent past.
- Have had a diagnosis of cervical cancer.
- Have HIV. You may also need screenings after age 65.
- Have a weakened immune system.
- Were exposed to a drug called DES (Diethylstilbestrol) before you were born. Between the years 1940-1971, DES was sometimes prescribed to prevent miscarriages. It was later linked to an increased risk of certain cancers in the female children exposed to it before birth.
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 will likely go away on their own.
If you are unsure whether you need a Pap smear, talk with your provider.
What happens during a Pap smear?
During a Pap smear:
- You will be asked to undress completely or from the waist down.
- You will lie on an exam table with your knees bent and your heels in footrests called stirrups.
- Your provider will gently insert a plastic or metal instrument called a speculum into your vagina. This helps to widen your vagina so that your cervix can be seen. This may cause a feeling of cramping or pressure.
- Your provider will then use a small, soft brush or swab to collect cells from the cervix. This doesn't usually hurt.
- The cell sample is sent to a lab for examination under a microscope.
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.
Will I need to do anything to prepare for the test?
You should not have a Pap smear while you are having your period because this may affect your results. A good time to have the test is about five days after the last day of your period. For two days before your test, you should not:
- Use tampons
- Use birth controlfoam, jelly, or cream
- Use other creams or medicines in your vagina
- Douche (rinse the vagina with water or other fluid)
- Have vaginal sex
Are there any risks to the test?
You may feel some mild discomfort during a Pap smear and have some very light bleeding afterward, but there are no known risks to having a Pap smear.
What do the results mean?
A Pap smear test could have the following results:
- Normal or "negative" result, which usually means that no abnormal changes were found in your cervix cells. 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.
- Unsatisfactory results, which may mean that the lab sample did not have enough cells, or the cells may have been clumped together or hidden by mucus. Your provider may ask you to come in for another test in a few months.
- Unclear results, which may mean that your cells look abnormal, but it's unclear if it's due to HPV. Unclear results could also be related to pregnancy, menopause, or an infection. An HPV test may help to find out if unclear results are due to HPV. Your provider will let you know if other tests need to be done.
- Abnormal or "positive" result, which usually means that 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.
A Pap smear doesn't diagnose cancer. It's also possible to receive a false-positive result, in which your results appear abnormal, but there are no precancerous or cancerous cells. Or you could have a false-negative, which happens when your results appear normal but there are precancer or cancerous cells.
Talk with your provider to learn what your Pap smear results mean. If they are concerned about your results, they may perform a colposcopy. This is an exam that uses a special magnifying instrument to look closely at your cervix to help diagnose or rule out cervical cancer.
Learn more about laboratory tests, reference ranges, and understanding results.
References
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