Female Reproductive Cancers Are Narrowing the Sex Gap in Life Expectancy

Women have faced higher cancer mortality than men between ages 35 and 60 in every generation since at least the 1930s despite women having a survival advantage for all other causes of death, according to a new cohort study of 264 million deaths across 20 high-income countries.¹ Eliminating female reproductive cancers would widen the female survival advantage by an average of 0.77 years across all countries studied.

For the study, researchers used data from the Human Mortality Database and the WHO Mortality Database, covering Australia, Canada, Japan, the United States, the United Kingdom, and 15 other low-mortality countries. In total, the dataset encompassed 264.4 million deaths, including 11.5 million from female reproductive cancers including breast, cervical, ovarian, uterine, vaginal, and vulvar.

Rather than relying on conventional period life expectancy, which reflects only current-year mortality rates, the researchers used a measure called the Truncated Cross-Sectional Average Length of Life (TCAL). TCAL is more sensitive to historical mortality trends because it incorporates the actual survival experience of all birth cohorts alive during the study period, rather than projecting a snapshot in time. This approach is particularly suited to detecting the long-term effects of cancer trends, screening programs, and treatment advances. Sex differences were then visualized using Lexis surfaces, a method that maps mortality patterns simultaneously across age, birth cohort, and calendar year.

Women are now expected to outlive men in every country on earth.² The female survival advantage was confirmed across all 20 countries in this study, but the magnitude varied considerably. The sex gap in TCAL ranged from 4.22 years in the Netherlands to 8.31 years in Hungary. Japan had the highest female TCAL (86.21 years), while Hungary had the lowest for both sexes.

Across every country examined, women held a clear mortality advantage for cardiovascular disease and external causes of death. The striking exception was cancer during the reproductive years. In what the authors described as a "distinct and stable age pattern," each successive cohort of women born since at least the 1930s experienced higher cancer mortality than men between the ages of 35 and 60. This was driven primarily by breast cancer and, secondarily, by gynecological cancers.

"These findings shift attention from the well-established male mortality disadvantage to a less recognized, biologically rooted, female vulnerability associated with reproductive function,” the authors explained.

In the US, women currently outlive men by 0.84 years in cancer-specific survival. Removing breast cancer alone would increase the sex gap in cancer-specific survival to 1.26 years. Removing all female reproductive cancers would add approximately 0.70 years to the overall US survival gap. Across all 20 countries, the average increase would be 0.77 years, ranging from 0.51 years in Japan to 0.96 years in Ireland.

Globally, cancer survival has improved substantially over recent decades due to screening, earlier detection, and treatment advances, and mortality from female reproductive cancers has declined in many high-income countries³. However, this study demonstrates that the underlying burden remains significant and consistent enough to measurably compress women's longevity advantage.¹ The authors characterize the elevated cancer risk during reproductive years as a "biological cost—or the price of reproduction," noting that estrogen and other sex hormones are central to the development of breast, endometrial, and certain ovarian cancers.

The findings carry practical implications. Country-level differences in the magnitude of female cancer disadvantage suggest that policy and clinical interventions matter. Where HPV vaccination programs have been broadly implemented, for instance, reductions in cervical cancer incidence are already measurable. This shows that prevention at a population level can shift the mortality curve.

References

1. Canudas-Romo V, Su W, Banks E, Timonin S. Female reproductive cancers and the sex gap in survival. JAMA Netw Open. 2026;9(3):e261256. doi:10.1001/jamanetworkopen.2026.1256

2. Barford A, Dorling D, Davey Smith G, Shaw M. Life expectancy: women now on top everywhere. BMJ. 2006;332(7545):808. doi:10.1136/bmj.332.7545.808

3. Sung H, Ferlay J, Siegel RL, et al. Global cancer statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2021;71(3):209-249. doi:10.3322/caac.21660