August 3, 2012
Dear Mayo Clinic:
I have had several abnormal Pap smears, and I'm worried about getting cervical cancer. How often should I be getting a Pap smear? Are there things I can do to prevent cervical cancer?
Getting regularly scheduled Pap smears is important for almost all women. Pap smears are particularly crucial for someone in your situation who has had abnormal results. Pap smears can often catch cervical cancer in its earliest stages, many times before it has even progressed to being cancer. Because of that, they are one of the most reliable prevention steps you can take to protect yourself against cervical cancer. If you are younger than 26, getting the human papillomavirus (HPV) vaccine will also help prevent cervical cancer.
In the early part of the twentieth century, cervical cancer was the leading cause of death in women. Today, cervical cancer is far down that list, thanks in large measure to Pap smears. The purpose of a Pap smear is to screen for cervical cancer. A Pap smear is usually done along with a pelvic exam and involves taking a sample of cervical cells. Samples are examined under a microscope to look for characteristic signs of cancer or precancerous cells. They are also probed to see if there is evidence of high-risk HPV.
The guidelines for how often women should get Pap smears have been changing rapidly over the last 10 years, causing some confusion. In the past, women were told to get a Pap smear every year. But the technology of the newer Pap smears has improved enough that once a year is not necessary for many women.
In general, women should start getting Pap smears when they turn 21, or three to five years after they start having sex, whichever comes first. For women ages 21 to 30 with normal Pap smear results, the guideline is to have the test every two years. For women 30 to 65 with past normal results, a Pap smear is recommended every three years.
Typically, women who have had a hysterectomy, those older than 65 and women who are not sexually active do not need Pap smears, as long as previous results have all been normal.
In your situation, however, when Pap smear results have been abnormal in the past — which means unusual or abnormal cells were discovered — there is no one-size-fits-all recommendation. You need to talk with your doctor about the types of cells that were found. Based on that, and your overall medical history, your doctor can recommend a schedule for Pap smears or colposcopy — a microscopic exam of the cervix via the vagina — that best fits your circumstances.
When cervical cancer is caught early, more than 90 percent of cases are curable. When a Pap smear finds precancerous cells, they usually can be effectively removed, preventing the disease by getting rid of the abnormal cells before they have a chance to become cancer.
In addition to Pap smears, the other key step you can take to prevent cervical cancer is to get the HPV vaccine. About 70 percent of all cervical cancer is caused by HPV, a sexually transmitted infection. The Centers for Disease Control and Prevention recommends the HPV vaccine for girls 11 to 12 years old. The series of three vaccinations can be started as early as age 9. The vaccine is also recommended for females 13 through 26 who have not been vaccinated. Side effects are uncommon and generally mild. The HPV vaccine has proven to be a safe, effective anti-cancer vaccine.
With regular Pap smears and proper follow-up, even women who have had abnormal Pap smear results can often be effectively protected against cervical cancer. Talk to your doctor about a specific care schedule and your prevention options.
— Keith Johansen, M.D., Obstetrics and Gynecology, Mayo Clinic, Rochester, Minn.