Before the widespread use of the PAP smear, cancer of the cervix was the leading cause of cancer death among women. The cervix is the opening of the uterus found in the back of the vagina.

While cervical cancer rates have fallen in the United States, the U.S. Centers for Disease Control and Prevention says there were more than 11,000 new cases of cervical cancer and nearly 4,000 deaths from the disease in 2005, the last year for which data are published. Through proper routine screening, nearly all of these deaths are preventable.

The vast majority of cases of cervical cancer are related to infection with certain strains of the human papilloma virus, also known as HPV. HPV can be transmitted to the cervix during sexual intercourse. Recent advances in cervical cancer screening include testing for the presence of HPV from specimens obtained during a PAP smear.

A PAP smear is a routine outpatient screening test that can be performed in a doctor's office. During the test, the doctor uses a metal or plastic instrument known as a speculum to widen the vagina to permit visualization of the cervix. A sample of cells then can be collected from the cervix and placed on a slide or into a liquid-filled container. In the laboratory, these cells are examined for any abnormalities.

To enhance the quality of the PAP sample for cervical cancer screening, women should schedule their PAP smear at a time outside their menstrual period. Sexual intercourse and the use of tampons, vaginal creams, foam or jelly also should be avoided for two days before the exam.

Regular PAP testing is recommended beginning three years after the onset of sexual intercourse or at age 21, whichever comes first. In addition to routine PAP testing, testing for HPV is recommended beginning at age 30 or for younger women whose PAP results are unclear.

For most women, PAP testing is recommended annually. However, in certain women at low risk who have had normal PAP tests repeatedly, the interval between PAP tests can be extended. Women older than 30 who are at low risk and have had three consecutive normal PAP smears may be able to extend the interval between PAP smears to every three years.

The PAP smear is an occasion for a comprehensive annual physical examination. While PAP testing may be less frequent in the low-risk group, yearly preventive health exams still are recommended.

PAP test results usually are available within two to three weeks after the examination. An abnormal PAP test result does not necessarily indicate the presence of cervical cancer. Women with abnormal PAP results should consult with their doctor about necessary follow-up.

Low-income women and those without health insurance may be eligible for a free or reduced cost PAP smear through the CDC's National Breast and Cervical Cancer Early Detection Program.

More information about eligibility is available by calling the Colorado Women's Wellness Connection at (866) 951-WELL.

Dr. Matthew A. Clark is a board-certified physician in internal medicine and pediatrics practicing at the Southern Ute Health Center in Ignacio.