Exploring Pap Smear Effectiveness

From the WebMD Archives

Nov. 19, 1999 (Minneapolis) -- Women probably don't give much thought to the device that's used to perform their routine Pap smear. But a new study by British researchers suggests that maybe they should.

Cervical screening is effective in decreasing incidence and death from invasive disease of the cervix. When a woman has a Pap, or cervical smear, test, clinicians obtain cells from the cervix using a collection device that helps the laboratory technician detect disease, such as cancer. The device may be a spatula, a cotton-tipped stick, a brush, or a combination of tools. The more cells collected, the easier it is for the Pap smear to be analyzed effectively in the lab. Although one collection device, known as the Ayre's spatula, is commonly used in the U.S., scientists in the U.K. now are questioning whether that method is best.

P. Martin-Hirsch, MD, of the department of obstetrics and gynecology at St. Mary's Hospital in the U.K., and his colleagues gathered data from 34 earlier studies comparing various devices and their ability to detect abnormalities within the cervix. Their findings suggest that design of the Ayre's tool is the "least effective device for cervical sampling." Instead, they suggest extended-tip spatulas. These have a longer tip than the Ayre's spatula that can reach into the cervix further and obtain more cells for evaluation.

But despite the magnitude of the British report, some U.S. experts aren't so sure of the significance of the report. Ephraim Resnik, MD, an obstetrician-gynecologist at Columbia-Presbyterian Medical Center of New York Presbyterian Hospital, tells WebMD that current U.S. methods of collecting cervical samples are "certainly yielding the results we're looking for." In addition, he says that most clinicians use a combination of tools rather than just one -- a point that these researchers did not emphasize.

Peter Schwartz, MD, agrees. "Using an endocervical device in association with a spatula gives much more accurate information about abnormalities within the cervix [than one tool alone]. Many elements make a Pap smear adequate and help provide a proper result," he tells WebMD. "In this day and age, a woman wants to be sure that her Pap smear is performed in an appropriate manner with a sample device that can adequately see the cervical canal. She can ask her doctor whether such a device is being used. Also, it's important that a woman is confident that the lab analyzing the smear has trained personnel." Schwartz is professor of obstetrics and gynecology and chief of gynecological oncology at Yale University School of Medicine and Yale-New Haven Hospital in Connecticut.


Schwartz says that all new screening in the U.S. focuses on the women receiving the Pap smear in the first place. He says it's important for women to remember that "the single largest group of women who get invasive cancer are women who don't have Pap smear screening, and this is true in every state."

So the next time a woman schedules her annual Pap smear, it may be a good idea to not only get to know the doctor who is performing the test, but also the device being used and the quality of the lab as well.

Vital Information:

  • A new British study shows that the most common device used in the U.S. to collect cervical cells for a Pap smear, the Ayre's spatula, may not be the best.
  • An extended-tip spatula may be a better choice, because it reaches further into the cervix and thus gathers more cells.
  • Critics of the study argue that many U.S. physicians use a combination of devices that does result in a reliable reading. Also, they say the problem is not how to perform a Pap smear, but rather convincing women to have the routine examination.
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