Study shows a slight breast cancer risk increase with progestogen-only birth control, comparable to combined oral methods

Summary: A UK study and meta-analysis examined breast cancer risk linked to hormonal contraceptives, emphasizing progestagen-only contraceptives in premenopausal women. Utilizing a nested case-control design with the Clinical Practice Research Datalink (CPRD), a primary care database, the study included 9,498 women under 50 diagnosed with invasive breast cancer between 1996 and 2017, and 18,171 closely matched controls. The meta-analysis merged CPRD findings with 12 observational studies on progestagen-only preparations.

The results revealed that current or recent use of combined oral contraceptives, oral progestagen-only contraceptives, injectable progestagen, and progestagen intrauterine devices all led to a similar increase in breast cancer risk. The 15-year absolute excess risk associated with five years of oral combined or progestagen-only contraceptive use ranged from 8 per 100,000 users aged 16-20 to 265 per 100,000 users aged 35-39. The study concluded that both contraceptive types were linked to a slight breast cancer risk increase, and these risks must be weighed against the benefits of contraceptive use during childbearing years.

Article: Combined and progestagen-only hormonal contraceptives and breast cancer risk: A UK nested case–control study and meta-analysis – PLOS Medicine

News Release: Study finds similar association of progestogen-only and combined hormonal contraceptives with breast cancer risk – PLOS

Commentary: Expert reaction to study looking at the association between hormonal contraceptive use and breast cancer incidence – Science Media Centre