Most contraceptives work inside the body by slowly releasing synthetic hormones. These are responsible for altering the conditions of the vagina and uterus, making it more difficult for sperm to enter or an egg to take hold, while at the same time tricking the body into thinking that ovulation has already occurred. Together this process has made hormonal contraception the most successful and popular form of birth control worldwide.
And while generally they have had little negative impact in terms of health, in fact proving to be a benefit for women suffering from acne while reducing ovarian cancer risk, new research suggests that using injectable contraceptives could significantly increase the risk of breast cancer.
Published in the journal Cancer Research, the United States-based study led by breast cancer epidemiologist Christopher Li, M.D., Ph.D., involved over 1,000 women aged between 20 and 44 who had been diagnosed with breast cancer, compared with 919 women with no history of the disease. 10% this group reported using the injectable contraceptive depomedroxyprogresterone acetate (DMPA). Recent usage of DMPA, within five years, for 12 months or longer resulted in a 2.2-fold increase risk of breast cancer.
“Although breast cancer is rare among young women and the elevated risk of breast cancer associated with DMPA appears to dissipate after discontinuation of use, our findings emphasize the importance of identifying the potential risks associated with specific forms of contraceptives given the number of available alternatives,” the researcher said, regarding the findings. “Our study [also] adds to the body of knowledge from international studies conducted in a diverse group of countries -- Kenya, New Zealand, Thailand, Mexico and Costa Rica -- which have shown that one of the risks associated with DMPA use may be an increased risk of breast cancer.”
This study is unique in that it’s one of the few to focus on and evaluate the associated breast cancer risk for young women with DMPA usage. Previously research had highlighted similar findings between progestin menopausal hormone therapy, that increased the cancer risk in postmenopausal women.
If you would like to find out more about the various contraceptive methods, you can find comprehensive information at OnlineClinic's Contraception Section.