Science strives for objectivity, but what happens when its methods are shaped by a single gender's perspective?
You've likely seen the headlines: "New wonder drug shows promise!" or "Groundbreaking treatment approved!" But here's a question rarely asked: groundbreaking for whom? For decades, the scientific community has operated on a silent assumption that what works for male bodies works equally well for female ones. This isn't merely an academic concern—it's a issue that directly impacts the safety and efficacy of medicines you use, the medical treatment you receive, and the very scientific knowledge we take for granted.
From the lab bench to the bedside, evidence reveals that systematic gender bias has compromised healthcare outcomes and limited our understanding of biology. The journey to uncover this bias reveals not just flaws in past practices, but a pathway to more rigorous, innovative, and equitable science for everyone.
To understand sexism in science, we must first distinguish between two often-confused concepts.
Sex refers to biological classification as male or female based on chromosomes and reproductive organs, while gender encompasses socially constructed roles, behaviors, and identities 1 . Sexism in biomedical research can affect both.
Following medical tragedies like thalidomide in the 1960s, regulators implemented strict protocols that systematically excluded pregnant women and women of childbearing potential from clinical trials 2 .
Openly negative attitudes, such as believing women are less capable in logical reasoning 3 .
Seemingly positive but ultimately limiting views, such as assuming women need special protection 3 .
Bias embedded in policies and practices of organizations 3 .
The extent of gender bias in scientific research is both staggering and well-documented.
Between 1997 and 2000, the U.S. Food and Drug Administration withdrew ten prescription drugs from the market because they posed greater health risks for women 1 . Eight of these drugs caused severe, life-threatening arrhythmia known as Torsade de Pointes, predominantly in women 1 .
Analysis across biological disciplines reveals a strong and persistent male bias in research design 1 . The table below illustrates the pronounced male bias across various scientific fields, based on analysis of published studies:
| Scientific Field | Ratio of Male-Only to Female-Only Studies |
|---|---|
| Neuroscience | 5.5:1 |
| Pharmacology | 5:1 |
| Physiology | 3.7:1 |
| Endocrinology | 3.5:1 |
| Zoology | 1.7:1 |
Table 1: Male bias in scientific research by discipline. Data shows consistent over-reliance on male subjects across biological sciences 1 .
This imbalance extends beyond animal studies to clinical research with humans:
A review found significant underrepresentation of women relative to their disease prevalence 4 .
An analysis of statin trials included only 16% women, despite women comprising 45% of actual users of these drugs 4 .
To understand how sex bias operates in practice, consider a compelling case study from respiratory research.
For decades, mechanisms of chronic cough had been studied exclusively in male guinea pigs 1 . The assumption was that findings from these male-only models would apply universally.
However, in 2015, an epidemiological study revealed a puzzling clinical reality: chronic hypersensitive cough predominantly affects postmenopausal women 1 . This presented a glaring contradiction—why was a female-predominant condition being studied exclusively in male animals?
| Research Characteristic | Traditional Male-Only Model | Inclusive Both-Sex Model |
|---|---|---|
| Subjects Used | Exclusive male guinea pigs | Both male and female guinea pigs |
| Assumed Variability | Assumed higher in females | Comparable variability between sexes |
| Clinical Relevance | Limited for female-predominant condition | High relevance for actual patient population |
| Statistical Power | Potentially limited generalizability | Robust, representative findings |
Table 2: Comparison of research models in chronic cough study 1 .
This case demonstrates how inaccurate assumptions about female variability (particularly concerns about hormonal cycles affecting results) had limited scientific understanding of a medically relevant condition 1 . By challenging these assumptions, researchers opened new pathways for understanding a condition that disproportionately affects women.
Addressing sexism in science requires both conceptual shifts and practical tools.
| Research Tool | Function in Gender-Sensitive Research |
|---|---|
| Both-Sex Models | Includes male and female cells, tissues, and animals in preliminary research 1 |
| Sex-Based Analysis | Analyzes data by sex to identify differential effects 1 |
| Hormonal Status Consideration | Accounts for hormonal cycles without excluding females 1 |
| Gender-Sensitive Protocols | Adapts methods to account for sex and gender differences 5 |
Table 3: Essential tools for combating sex bias in biomedical research 1 5 .
In 2016, the U.S. National Institutes of Health implemented a policy requiring scientists to consider sex as a biological variable in their research designs 1 .
This represented a significant step toward institutionalizing better practices. The policy acknowledges that including both sexes in research is not merely about fairness—it's about scientific rigor and comprehensive knowledge.
The movement to eliminate gender bias from science is gaining momentum, but significant challenges remain.
Research using Implicit Association Tests (IAT) found that male scientists exhibited a strong male-science association, similar to levels in the general population, while female researchers showed significantly lower bias 6 . This suggests that diversifying the scientific workforce may be key to addressing biased research questions and methodologies.
That routinely include both sexes in studies and analyze data by sex 1 .
Faced by pregnant women in low-and middle-income countries who bear a disproportionate burden of maternal mortality 2 .
That deny pregnant women autonomy in deciding whether to participate in research 2 .
The entire research ecosystem, leading to more innovative and comprehensive science 2 .
As we look to the future, the question is not merely "Is science sexist?" but "How can science become more equitable, rigorous, and relevant for all?" The answers will shape the next generation of medical breakthroughs and determine who benefits from them.
By acknowledging and addressing historical biases, we stand on the threshold of a more inclusive and effective scientific era—one that truly serves all of humanity, in all its diversity.