The pill has a possible new side effect: preventing cancer. Women who took oral contraceptives for less than eight years have up to a 12% lower risk of developing the disease, according to a new British study, one of the largest ever conducted. The risk of developing bowel and rectal, uterine and ovarian cancers was most reduced.
But those using the pill for longer—roughly a quarter of users—saw the opposite effect, with risk skyrocketing 22%. Despite that danger, researchers believe the study provides reassurance for many women, especially first-generation contraceptive users now entering prime cancer risk years.