There has been a great deal of controversy about the safety of birth control pills for decades. New research shows that the recent use of some types of birth control pills may increase the risk of breast cancer reported the American Association for Cancer Research on August 1, 2014. According to this research women who recently used birth control pills which contain high-dose estrogen and a few other formulations had an increased risk for breast cancer. Other woman using other birth control formulations did not have this increased breast cancer risk.
Elisabeth F. Beaber, PhD, MPH, a staff scientist in the Public Health Sciences Division of Fred Hutchinson Cancer Research Center in Seattle, Washington, says the results of this research suggest that the use of contemporary oral contraceptives in the past year has an association with increased breast cancer risk relative to never or former oral contraceptive use. This risk appears to vary by oral contraceptive formulation.
Beaber says these results need confirmation and should be interpreted with caution. Breast cancer is only rarely seen among young women and there are many established health benefits which are associated with oral contraceptive use that must be considered. Furthermore, prior studies have suggested that the increased risk which is associated with recent oral contraceptive use decreases after the oral contraceptives are stopped.
In this study recent oral contraceptive use was observed to increase breast cancer risk by 50 percent in comparison with never or former use. Breast cancer risk was increased 2.7-fold with birth control pills containing high-dose estrogen. Birth control pills with moderate-dose estrogen increased the risk 1.6-fold. Pills which contain ethynodiol diacetate increased the risk 2.6-fold, and triphasic combination pills which contain an average of 0.75 milligrams of norethindrone increased this risk 3.1-fold. Low-dose estrogen birth control pills did not increase breast cancer risk.
This study has been published in the journal Cancer Research, a journal of the American Association for Cancer Research. Previous studies of oral contraceptives and breast cancer have indicated that recent use of birth control pills slightly increases breast cancer risk, but most studies have depended on self-reported use and did not examine contemporary oral contraceptive formulations. The results of this study have suggested that the recent use of contemporary oral contraceptives is associated with an increased risk of breast cancer. Considerations of the recognized health benefits and potential risks of birth control pills should keep this in mind as research dealing with this matter continues.