Ask a Best Doctor: When Should I Get a Pap Smear?

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Question: I'm confused by the ever-changing pap smear guidelines. How often do I actually need to get one?

Answer: Dr. Lynn Friedman, OB-GYN at Mt. Sinai Hospital.  

The answer isn't an uncomplicated one — and, as always, ask your own Ob-Gyn what your personal health details require — but it's certainly easier to comprehend than the seemingly constant news reports citing one study or another that recommends different intervals between exams.

A simple start: If you're under 21, you don't need a pap smear, even if you're sexually active. "From the time of first exposure to a significant lesion is many years, and women under age 24, with normal immunity, basically never develop significant lesions," says Dr. Friedman, "so they do not need to be screened." Once you're 21, until age 29, a pap screening alone (without the accompanying DNA test for the human papilloma virus) is recommended every three years — you're still at a low risk for significant HPV-related lesions and your immune system is good at containing the virus if you are exposed to it. Starting between age 30 to 35, Friedman says both a pap and DNA test for HPV are recommended. If your cervical cells appear normal on the pap smear and the DNA test is normal, you can space pap smears out to every three to five years; if the pap is normal but HPV is present (meaning you've tested positive for "dormant" virus), both tests should be repeated in one year; if both tests are negative and HPV has been cleared, a three- to five-year spacing for paps is then recommended as well. However, if the pap is normal and the virus still positive, an evaluation of your cervical cells and biopsy will be performed, "to make sure the pap smear did not miss anything," says Dr. Friedman. "According to the literature, 20 percent of women will have a significant finding upon that evaluation that was missed on the pap smear."  If you have both an abnormal pap and test positive for HPV,  your doctor should evaluate you immediately. 

"The thought process here is that by the time a woman reaches her mid thirties, the majority of us have been exposed to HPV, because the virus is so prevalent in the general population. Many of us have been exposed and have cleared the virus by our mid-thirties," Dr. Friedman explains. "The idea is to narrow down who still has it, and follow those women more carefully, and let the women who have cleared the virus be followed less frequently." Women with negative evaluations for three consecutive years can stop screening at age 65. And remember, these are still just guidelines: You may opt to screen more frequently if you and your doctor decide it's what's best based on your personal risk factors.

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