Lack of representation in clinical trials may harm women’s health

Author(s): Jesslyn Thay , Date: 08 March 2023

International Women’s Day occurs annually on 8th March. A day to highlight global inequities faced by women throughout society- such as limited access to health services, lower socioeconomic status or political injustice. 

The medical research and health spheres have always been traditionally male-led, with specific women’s health conditions receiving less attention, research investment and funding.

Furthermore, women are often underrepresented in clinical trials for non-reproductive health conditions, this has wide implications regarding potentially safety risks of new medical treatments and drugs, but also questions effectiveness of novel therapies if they are only tested on male physiologies. 

Currently the impact of women being underrepresented in clinical trials is vast, from concerns about safety to healthcare research not working on women’s symptoms for the same ‘gender-neutral’ health conditions, as Tlalit Bussi Tel Tzure  for Forbes states. 

There is also a lack of research into the impacts of ensuring studies are fairly balanced between genders of participants. Even in research for treating long-term diseases which are more prevalent in the female population, such as type 2 diabetes and other metabolic disorders, women are distinctly in the minority during clinical pharmaceutical or therapeutic trials.

This has major impact for wide scale public health and provision of health services, particularly long-term drug therapies to manage chronic conditions in women which may have hidden safety concerns due to lack of diversity in testing. 

While US legislation states empirically that “Clinical studies must ensure women are represented, which means we must create and implement policies ensuring gender equity in study design, recruitment and analysis. Since a 1993 NIH ruling, federally-funded drug trials and other clinical research have been required to include female participants. They must also determine whether the treatment being tested affects females differently than males.” 

Similar rules apply for research in Canada, Ireland and Germany, with established policies and codes of practice that require the integration of sex and gender analyses in competitive research grants and publications in journals.

In Sweden, the Karolinska Institutet's Centre for Gender Medicine supports research and education with a particular focus on how the promotion and implementation of sex and gender analyses can drive innovation in health care ( 

There is almost an absence of women of colour being represented in clinical trials worldwide, despite women of colour being some of the most disadvantaged individuals when it comes to disease, diagnosis, treatment and therapy.

A review published in Cell Reports Medicine last year , wrote “The total percentage of participants (of which women comprise less than half) in oncology trials who were Black or African American over the years 2017–2020 ranged from 2% to 5%, and of Hispanic or Latino ethnicity from 4% to 6%. These numbers are in stark contrast to the demographics of the US population of which 12.1% are Black or African American and 18.7% are Hispanic or Latino, and the largest racial and ethnic minorities in the country, respectively.3 Not only are women underrepresented in certain therapeutic areas, but women of color are disproportionately excluded.” 

By incorporating sex and gender dimensions in health research we increase understanding of the risk factors and causes of disease and how best to prevent and manage conditions, as well as reduce potential harms for women and men. Therefore, developing health policies and practices to facilitate incorporating sex and gender dimensions in health research are important to enable the best outcomes.



Bierer BE, Meloney LG, Ahmed HR, White SA. Advancing the inclusion of underrepresented women in clinical research. (2022) Cell Rep Med. 2022 Mar 7;3(4):100553. doi: 10.1016/j.xcrm.2022.100553. PMID: 35492242; PMCID: PMC9043984. 

NIH Office of Research on Women's Health (ORWH) NIH Inclusion Outreach Toolkit: How to Engage, Recruit, and Retain Women in Clinical Research [accessed: 8/03/23] 

Tlalit Bussi Tel Tzure
 (2023) Ignored and Underrepresented: The Impact Of Excluding Women In Healthcare Research. Forbes [accessed 8/03/23]