Introduction
Across countries and income levels, the World Health Organization's goal of achieving "health for all" remains unmet. In fact, the World Health Organization and World Bank(2023) estimated that, as of 2021, roughly 4.5 billion people worldwide lacked essential health services. Women in particular face distinct health challenges and associated difficulties, especially when compared to men. For instance, in 2023, over 260,000 women died from pregnancy-related causes - the vast majority in low- and lower-middle-income countries, and most of these deaths were preventable (WHO, 2025). I choose gender as the entry point because it is the most visible and persistent axis of inequity in both access to care and scientific knowledge.
Gender inequities not only deny women care, but also distort the science that guides care. Here, gender is understood as the social norms, roles, and power relations associated with being a woman, man, or gender non-conforming. This essay examines gender as a social determinant of health through two dimensions: women’s unpaid work and disparities in the health knowledge base. The discussion begins with a literature review, proceeds to mechanisms of inequity, and ends with concrete examples and feasible solutions.
Literature review of gender health inequalities
Access Gaps in Women’s Health
Despite progress toward universal health coverage (UHC), women’s access to essential health services remains constrained. In 2021, an estimated 2 billion people globally faced financial hardship due to health costs, with services central to women’s health across the life course under particular strain (WHO & World Bank, 2023). For example, women around the world continue to have inadequate access to contraception, antenatal care, and chronic disease management. In addition to service gaps, gender-related risks also manifest as violence: nearly one in three women are estimated to experience physical or sexual intimate-partner violence in their lifetimes (Sardinha et al., 2022). The consequences are often fatal—48,800 women were killed by partners or family members in 2022, a number that rose to approximately 51,100 in 2023 (UN Women & UNODC, 2023; UNODC, 2024). This means that gaps in essential services and the burden of violence directly translate into preventable female deaths.
Structural Power and the Burden of Unpaid Care
Contemporary theories help explain why these persistent gaps in women’s health continue to emerge. Ecosocial theorist Krieger (2001, 2012) traces how power relations and material conditions become embodied over the life course, calling for multi-level, historically informed analyses of discrimination and health. One clear example is women’s disproportionate share of unpaid care work: they perform an estimated 76.2% of all unpaid care hours, leaving them with fewer opportunities for paid employment, schooling, or clinic visits. At the structural level, women also lack equal legal protections in areas such as mobility, pay, childcare, and entrepreneurship. Compared with men, they enjoy fewer rights and protections, which reduces their earnings and bargaining power and, in turn, negatively affects care-seeking behaviors (Wingood & DiClemente, 2000).
These structural inequalities are reproduced through everyday institutions, including households and labor markets. Established sociological studies demonstrate how women’s disproportionate responsibility for unpaid care and routine domestic work creates "time-poverty," delaying access to care and elevating chronic stress (Annandale & Hunt, 2000). Moreover, simple status categories—such as marital status or employment—often obscure the complex biographies and overlapping roles that significantly shape women’s health outcomes (Annandale & Hunt, 2000). This means that structural inequalities, reinforced by women’s disproportionate unpaid care work and everyday institutional arrangements, systematically reproduce health disadvantages for women.
Evidence Bias in Medical Research and Practice
In addition, the knowledge base guiding clinical care has long been built on male-skewed evidence. Classic audits found that, among single-sex biomedical studies, male animals were used more than four times as often as females (Beery & Zucker, 2011), and more recent reviews confirm that this bias persists in preclinical research (Karp et al., 2018). These upstream gaps carry over to trials. For example, in an analysis of 740 cardiovascular trials (862,652 participants, 2010–2017), women comprised only 38.2% of enrollees (Jin et al., 2020). In randomized controlled trials of cardiac resynchronization devices, only 23% of participants were women, and only half of trials reported sex-specific outcomes—despite evidence from two major studies that women derived greater benefit (Ahmad et al., 2022). Recent meta-research continues to find systemic under-representation and under-reporting by sex across clinical areas (Spiering et al., 2024).
These imbalances contribute to diagnostic errors, dosing problems, and avoidable harm for women. In some cases, regulators have even had to adjust recommendations after approval. For instance, in 2013 the U.S. FDA halved the recommended dose of zolpidem for women after higher residual blood levels caused next-day impairment predominantly in female patients (FDA, 2013). Historically, many safety signals have only surfaced after drugs reached the market. At the population level, women consistently experience higher risk of adverse drug reactions (ADRs) than men (Rademaker, 2001). Even worse, more recent research suggests that sex differences exist in nearly half of commonly used drugs, with women experiencing almost twice the risk of ADRs across drug classes (Zucker & Prendergast, 2020; Lapeyre-Mestre, 2019; Shan et al., 2023). This means that persistent evidence bias and the neglect of gender dynamics in healthcare delivery expose women to preventable harms, from misdiagnosis and adverse drug reactions to higher mortality risks.
Examples and proposed solutions
The gender division makes women engaged in a large number of unpaid care jobs. Women perform much more unpaid care than men, which limits their access to health care and reduces transportation and medical expenses for disposable income. Women also face a gender pay gap of up to 24 percentage points in the healthcare labor market. The gender division of labor is not only an abstract cultural phenomenon, but also a system of resource allocation.
Cash Transfers and Service Adaptations
From the perspective of social policy, gender equality is not only a matter of rights but also an issue of health equity within the framework of resource allocation. When tangible resources are directly placed under women’s control, they have the potential to reshape power structures and alleviate the “time poverty” and economic constraints that drive health inequalities. A specific example is Brazil’s conditional cash transfer (CCT) program—the Family Grant Program (Bolsa Família, BFP). The program links welfare to health behaviors and transfers cash to women in most beneficiary households. Alves et al. (2023) found that participation in BFP helps overcome transportation and cost barriers, stabilize household consumption, and promote antenatal care and institutional childbirth—clearly illustrating how resource allocation can determine individual health outcomes.
The experience of the Brazilian project shows that providing more cash transfers and financial support to women can reduce the gender gap in health. However, economic protection alone may not be sufficient and must be combined with a reliable supply of health services. Insurance reform and the abolition of user fees can truly improve utilization only when clinics are fully staffed and adequately supplied. Rwanda's community health insurance illustrates this well, showing that reducing out-of-pocket costs (OOP) can both increase access to maternal health services and reduce catastrophic spending. In addition, health care must be adapted to groups with limited time. Extending clinic hours, integrating services, and subsidizing transport vouchers are all practical measures. For example, in the Oyam district of northern Uganda, a transportation voucher program provided pregnant women with round-trip support to designated clinics for prenatal, childbirth, and postnatal care. Compared to similar areas without transportation vouchers, institutional delivery rates increased by 42.9% and postnatal care within six weeks increased by 49.2% (Massavon, 2017).
Various service projects at the community level have also shown positive results. In western Kenya, a randomized intervention experiment found that providing pregnant women with cash vouchers, transport subsidies, and SMS reminders significantly increased the proportion of births in health facilities (Grépin et al., 2019). This suggests that economic and service support at the grassroots level can effectively reduce women's time and transportation barriers, and complement the formal health system.
In conclusion, advancing health equality between men and women requires action on three fronts. Cash protection directly empowers women by easing financial and time constraints; service improvement to remove structural obstacles through supply-side reform; Research reform rebuilds the upstream evidence base to ensure that women's health needs are scientifically recognized and responded to. Combined, these three strategies can not only lead to short-term improvements in service utilization for women, but also promote institutional equality in the health system in the long term.
Reforming the Evidence Base for Gender Equity
A deeper reason for gender health inequality is that there may be misconceptions and biases inherently in the production of medical knowledge. When research systematically privileges male bodies, the resulting evidence base embeds structural bias into prevention, diagnosis, and treatment. Addressing this requires reforms across the evidence-to-care chain. One essential step is mandating sex balance and sex-disaggregated analysis in discovery and trials. Some progress exists: for example, the NIH’s Sex as a Biological Variable (SABV) policy now requires sex to be incorporated into study design, analysis, and reporting in both vertebrate animal and human research. Applications proposing single-sex designs must include strong scientific justification, and peer reviewers are explicitly instructed to evaluate SABV as part of rigor and reproducibility.
Journals have also reinforced these shifts. The Sex and Gender Equity in Research (SAGER) reporting guidelines are now embedded in major editorial ecosystems, including EQUATOR and the NLM research reporting lists. Large publishers such as Springer and Nature require SAGER-compliant submissions, which mandate clear use of the terms sex and gender and disclosure of the sex being studied (Heidari et al., 2016; EASE SAGER; Springer policy page).
However, significant gaps still exist. Policies have increased the use of female people in research, but sex-specific analyses are still rare. In cardiovascular trials, women continue to be under-represented: a 2024 review found no improvement over time, with 62% of trials still under-enrolling women relative to disease burden. Detecting treatment-by-sex interactions also requires much larger sample sizes than detecting main effects. Yet many studies add women without revising their original power calculations. Reviews caution that interaction tests are routinely underpowered and call for adequately powered designs whenever sex differences are plausible.
These imbalances contribute to diagnostic errors, inappropriate dosing, and preventable harm for women. In 2013, the U.S. Food and Drug Administration halved the recommended dose of zolpidem (Ambien) for women after finding slower metabolism led to next-day impairment and traffic accidents. This case shows how male-biased trials can produce real-world risks. Regulators have since focused mainly on sex-based enrollment targets, yet gender identity and broader social determinants remain largely absent from trial design and labeling.
Based on these limitations, the following measures are suggested. First, the SAGER guidelines must become non-negotiable. Editors could adopt a checklist gate, requiring submissions to define sex and gender terms and to present sex-disaggregated outcomes—or provide a clear justification for not doing so. Second, interaction testing should become a design objective in conditions with known or plausible sex differences. Protocols should include a priori sex-stratified hypotheses, sample-size calculations for interaction effects, and pre-specified meta-analyses across trials when single studies are insufficiently powered. This means that without enforceable standards, research will continue to fail women in evidence-based care.
Conclusion
This essay has approached gender inequalities in health as structural determinants, showing how both the division of labour and the production of medical knowledge systematically reproduce disadvantage for women. First, the gendered division of labour creates time-poverty and income constraints that limit women’s ability to obtain health services. Second, a male-dominated knowledge base contributes to diagnostic errors, mis-dosing, and avoidable harm. There are, however, practical solutions. Predictable, woman-directed social protection, such as Brazil’s CCT, can help reduce gender disparities. Likewise, making Sex as a Biological Variable (SABV) and enforceable SAGER standards mandatory would strengthen the evidence base. If we can redesign health systems with gender equity at their core, we will not only save women’s lives but bring the world closer to the WHO’s vision of Health for All.
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