Even though women make up half of the world’s population, much of what we know about disease and treatment is based on men. Historically, medical research has been male dominated—both in terms of study subjects and researchers. The assumption that women’s health can simply be extrapolated from research on men is deeply flawed. Women are not just smaller men—our bodies have unique physiology, hormonal environments, and genetic expressions that affect everything from disease symptoms to drug metabolism.
Men and women experience many of the same diseases, but the way those diseases manifest—and how the body responds to treatment—can be vastly different. Autoimmune diseases overwhelmingly affect women 1, with nearly 80% of cases occurring in women. Yet, in cancer immunotherapy—where the immune system is leveraged to fight tumours—men often respond more favourably.2 Women’s immune systems tend to be more reactive, which may explain both their higher rates of autoimmune disease and their different responses to immunotherapy. Despite these biological differences, most clinical trials fail to account for them, leading to treatments designed around male physiology—treatments that may be less effective, carry higher risks, or cause more severe side effects in women.
Without sex specific research, are we designing cancer treatments that may not work as well for half the population ?
Men and women respond differently to cancer treatments. Variations in metabolism, hormone levels, and body composition can affect the efficacy and side effects of therapies.3
Women experience more severe side effects from some cancer treatments. For example, chemotherapy-related toxicities are often worse in women, yet most drug trials fail to analyze sex differences in side effect profiles.4
Women remain underrepresented in clinical trials. Treatments and guidelines are often developed based on male-centric data, making them less applicable to women and leading to disparities in care and outcomes.5
While the United States attempts to push women backward with legislation like the Safeguard American Voter Eligibility (SAVE) Act (amongst others), which could strip 69 million married women of their right to vote simply because they changed their last name after marriage 6, we must recognize the broader pattern. When women are not counted, we do not count. The same logic applies to our health: when we are excluded from research, we receive worse care.
Canada, like women in medical research, is often dismissed as too small to matter. Pharmaceutical companies tell us we are just 2% of the global market, as if that justifies exclusion from major investments. Dismissing either as insignificant is not just inaccurate—it’s dangerous. This exclusion leads to gaps in science, worse health outcomes, and missed opportunities for innovation.
Canada believes in diplomacy, we believe in science, and more importantly we believe in facts. We may be small, but we are mighty and women are not small men.
On International Women's Day, the cancer collaborative is asking Canada to step up and take action
Investment in sex specific research to ensure treatments work for the people who take them
A global commitment to science, equity, and evidence based healthcare
Mandatory collection and reporting of sex disaggregated data to close the sex gap in research and healthcare
Policies that recognize and protect women’s rights, rather than erasing them
This isn’t about making room at the table—it’s about rebuilding the table to make space for women’s health in healthcare.
references
Vera R, Juan-Vidal O, Safont-Aguilera MJ, de la Peña FA, Del Alba AG. Sex differences in the diagnosis, treatment and prognosis of cancer: the rationale for an individualised approach. Clin Transl Oncol. 2023 Jul;25(7):2069-2076. doi: 10.1007/s12094-023-03112-w. Epub 2023 Feb 18. PMID: 36802013; PMCID: PMC10250517
Daitch, V., Turjeman, A., Poran, I. et al. Underrepresentation of women in randomized controlled trials: a systematic review and meta-analysis. Trials 23, 1038 (2022). https://doi.org/10.1186/s13063-022-07004-2
Clark, Sophie. Married Women Could Be Stopped From Voting Under SAVE Act. Newsweek 2025 Feb 11