Why you don't need a pap smear every year

I find it funny that when new breast cancer screening guidelines were introduced a couple of years ago there was an uproar. It was on the nightly news, countless articles were published, leading breast cancer authorities were interviewed, patients gave their testimonies and so on. But when the pap smear guidelines were changed around the same time....nothing. You could have heard the crickets chirping. Perhaps it's because no one likes to get a pap test, but I have not heard much complaining about the changes! A lot of women are still confused, however, about what the new guidelines mean for them. So, here are the most important points. 1. Pap smears are no longer recommended for anyone under the age of 21. 2. Women between 21 and 30 should get a pap smear every 3 years. 3. Women between 30 and 65 should get a pap smear and HPV testing every 5 years (a pap smear alone every 3 years is also acceptable). 4. Women over 65 with no history of cervical cancer or serious precancerous lesions should stop getting pap smears. Previously, all women over 18 or within 3 years of the onset of sexual activity were getting pap smears every year. So why the changes? Wouldn't we want to screen for cervical cancer as much as possible? Isn't screening a good thing? To understand the rationale behind the changes, you have to understand the natural history of cervical cancer. The cervix is a cylinder shaped neck of tissue connecting the uterus to the vagina. It dilates slightly to allow the passage of menstrual blood and a lot to allow passage of a baby! There is an area on the cervix where the cells transform from the cells that line the vagina to those that line the inside of the cervix. This is called the transformation zone and it is susceptible to infection by a sexually transmitted disease called Human Papilloma Virus (HPV). HPV causes cellular changes and over time these can accumulate and lead to cancer. Young women have larger transformation zones and are more vulnerable to HPV and therefore to these changes. But younger women are also more likely to clear the virus and repair those changes. When we were screening young women yearly, many of them who were found to have precancerous lesions received unncessary treatment for them because they would never have become cancer. Unnecessary treatment can lead to pain and bleeding from procedures, anxiety and pregnancy complications. Women who have had a LEEP (a procedure that cuts out an abnormal area of the cervix) have higher rates of preterm birth, low birth weight babies and premature ruputure of their membranes. Women over 30 are less likely to clear HPV infections and have higher rates of progression to serious precancerous and cancerous lesions which is why HPV testing is recommended in this age group. The longer screening intervals makes sense when you think about the fact that it usually takes several years to accumulate enough changes in the cervical cells to become cancer. It is exceedingly rare to go from a normal pap smear to cervical cancer in 1 year. Screening too frequently can also lead to false positive results. So embrace the fact that this is a test most of us can get by with having less often. Oh and by the way, ladies, we owe a debt of eternal gratitude to Dr. Papanicolaou's wife Mary who let him take the first cervical smears that allowed him to develop what we now call the pap test. Prior to its introduction in the late 1940s, cervical cancer was the #1 killer of women. Thank you Mary!