The study authors estimate that 400 000 cases of endometrial cancer before the age of 75 years, out of an estimated total of 3•4 million endometrial cancers, may have been prevented over the past 50 years (1965–2014) by oral contraceptives, including 200 000 in the past decade (2005–14).
An accompanying editorial notes that even women who use oral contraceptives in their 20s continue to benefit from protection from endometrial cancer into their 60s, when the incidence of endometrial cancer starts to increase. Furthermore, the relative reduction in risk was found to be constant across a range of risk factors for endometrial cancer.
The available data do not allow for specific recommendations for chemoprevention to be made but help in balancing the benefits and harms of oral contraceptives.