A Pap smear can detect cervical cancer and signs of uterine and ovarian cancers. The problem is that Pap smears too often give false positives, suggesting there’s an issue when there isn’t one. These, in turn, can lead to unnecessary further testing and removal of healthy tissue, as well as needless treatment that could create pregnancy complications down the road. Between the ages of 21 and 29 you probably only need a Pap every other year, and one every three years from 30 on.

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