Ask Your Family Doctor

Developed by the College of Family Physicians of Canada

What is a Pap smear?

A Pap smear is a simple test that can help prevent cancer of the cervix. Pap smear testing saves lives. If women had regular pap tests, 90% of cancer of the cervix would be prevented. During a Pap smear, your doctor takes a sample of cells from your cervix to be tested. The cervix is the part of your uterus (womb) where blood flows through when you have a menstrual period.

To take the sample, your doctor will gently put a special instrument called a speculum into your vagina. This helps open your vagina so the doctor can see your cervix and a sample can be taken. Your doctor may gently clean your cervix with a cotton swab and then collect a sample of cells from your cervix with a small brush, a tiny spatula or a cotton swab. This sample is put on a glass slide and sent to a laboratory to be checked This exam only takes a few minutes. It is very important to stay relaxed to help make it more comfortable for you.

What is the sample checked for?

The cells are checked for signs that they're changing from normal. Cells go through a slow (many months or years) series of changes before they turn into cancer. Pap smears can show if your cells are going through these changes long before you have cancer. Cervical cancer is not life-threatening if it's caught early. This is why getting your Pap smear regularly is so important. The test results will be back in a few days to a few weeks. You should ask your doctor how you could get your Pap test results.

What do the results mean?

Pap tests can be reported different ways. A negative Pap test is one that is reported as satisfactory and shows normal cells. Some pap tests are not satisfactory or have abnormal cells and have to be repeated. A positive Pap smear means that your results aren't normal but does not always mean you have cancer. A positive Pap smear can be a sign of a number of changes in the cells on your cervix:

The results of your Pap smear may be abnormal if the cells on your cervix are inflamed (irritated). This can be caused by an infection of the cervix, including a yeast infection, infection with the human papillomavirus (HPV) or herpes virus, or many other infections.

Changes in cells that are very early signs of cancer can also cause your Pap smear to be abnormal.

Finally a Pap smear can also detect cancer itself.

How reliable is the test?

No test is perfect but the Pap smear is very reliable. When a Pap smear is positive, abnormal cells are present about 95% of the time. The other 5% of the time, no abnormal cells are present even though the Pap smear is positive. When a Pap smear is negative, there can still be abnormal cells that are missed by the test. If you have abnormal cells, the test may miss them 30% of the time and catch them 70% of the time. This is one of the reasons that regular Pap smears are so important.

Sometimes the test may need to be redone because not enough cells were gathered in the sample. The laboratory should be able to see when there aren't enough cells on the slide, and then tell your doctor. Even though the Pap smear isn't 100% accurate, it has helped drastically lower the number of women who die from cancer of the cervix. The Pap smear is very worthwhile and is still the only test to check for the early changes in the cells that might lead to cancer.

Can I help make the test more accurate?

Yes. You can help make the test more accurate by not douching or using a feminine deodorant; birth control creams or jellies for 48 hours and by not having sex for 24 hours before the test. Plan to have your test done at a time when you aren't having your menstrual period.

When should I begin having Pap smears?

You should have your first Pap smear when you start having sex or by the time you reach age 18. Keep having Pap smears throughout your life, even after you've gone through menopause.

How often should I have a Pap smear?

Some physicians think you should have a Pap smear every year. Others think you should have a Pap smear once a year until you've had a least three normal ones. After this, you should have a Pap smear at least every three years as long as they stay normal. Ask your doctor what they think about how often you need a Pap smear.

Certain things may put you at higher risk of cervical cancer. Your doctor will consider these things when recommending how often you should have a Pap smear. Also talk with your doctor about how often you need a Pap smear if you're older than 65. If you have irregular bleeding or very heavy periods, or bleeding after sex or after menopause, see your doctor. You may need a Pap smear as a part of the exam for these symptoms. If you have had a hysterectomy ask your doctor if you still need to have Pap smears.

What puts me at risk of cervical cancer?

The main risk factors for cervical cancer are related to sexual practices. Much of this risk seems to be related to diseases that can be passed by having sex. These sexually transmitted infections (STIs) may affect your cells in a way that makes them more likely to undergo changes that can lead to cancer. These diseases include HPV, herpes, gonorrhea, and chlamydia. HPV seems to be very closely connected with these changes.

What is HPV?

HPV is the virus that causes warts. It's very common. There are many types of. Certain types cause warts on the hands or feet. Other types cause wart-like growths on the cervix, in the vagina or anus, or on the penis, scrotum ("balls"), groin or thighs. These types of HPV are called genital HPV. They are (sexually transmitted infections). Often, the eye can't see the effects of HPV, but the effects can cause changes in cells. Many women who have positive Pap smears have genital HPV.

What happens if I have a positive Pap smear?

If the results of your Pap smear are positive, your doctor may want to do another Pap smear test for infections or may want you to have a colposcopy.

What is colposcopy?

Colposcopy is an easy test that gives your doctor a better look at your cervix and allows him or her to take samples of cervix tissue (biopsies).
Before the colposcopy, the doctor puts a special solution on your cervix. This causes the abnormal cells to turn white. The doctor then looks at your cervix through a colposcope. A colposcope is a special instrument that shines a light on your cervix and magnifies it so that the doctor can see it better.
Colposcopy and biopsy are usually done in a doctor's office or a special clinic. Colposcopy doesn't feel much different from a Pap smear. But some women feel a little cramping and bleed a little bit afterward.

How are the abnormal cells treated?

If the tests show that you have some changes on your cervix that could lead to cancer, your doctor may recommend cryosurgery, laser surgery or the LEEP procedure. These treatments remove the affected cells. Cryosurgery freezes cells off. Laser surgery burns or vaporizes the cells off. LEEP (Loop Electrosurgical Excision Procedure) removes the cells using a wire loop.

You may have to have treatment more than once because the treatments don't always reach all of the affected cells the first time. Your doctor will probably want to do Pap smears more often after treatment to see if the treatment has worked and to keep an eye out for any more changes of your cervix.

Is there anything I can do to avoid getting cervical cancer?

You may be able to reduce your risk of cervical cancer by:

	Not starting to have sex early (before age 20).
	Remembering that, if you choose to have sex, the only truly safe sex partner is one who doesn't have an STI and has only ever had sex with you.
	Limiting the number of sex partners you have may also help.
	Using latex condoms (rubbers) may help prevent the spread of HPV and other STIs.
	Using a spermicide (sperm-killer) that contains nonoxynol-9 along with condoms may increase this protection. But using condoms is not 100% effective in protecting you. For example, HPV can be on the scrotum, thigh and other places not covered by condoms.
	Not smoking may also help reduce your risk of cervical cancer.

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Revised 2007 The College of Family Physicians of Canada

This information provides a general overview on this topic and may not apply to everyone. To find out if this information applies to you and to get more information on this subject, talk to your family doctor. This health education material has been favorably reviewed by the Patient Education Review Committee of the College of Family Physicians of Canada: Dr Cathy MacLean, Halifax, NS (Scientific Editor) Dr C. Richard Fischer, Pickering, ON Dr Patrice Laplante, Fleurimont, QC Dr Richard Moffatt, Red Deer, AB Dr David Nunn, Kentville, NS Dr Cornelius Woelk, Winkler, MB The College of Family Physicians of Canada, one of the nation's largest medical groups, is committed to promoting and maintaining high standards for family physicians - the doctors who provide ongoing, comprehensive care for people of all ages. This patient education information was developed by The College of Family Physicians of Canada in cooperation with the American Academy of Family Physicians.

Support for this program has been provided by an educational grant to the Research and Education Foundation by Scotiabank.