Women’s participation in science, technology, engineering, and mathematics (STEM) remains uneven despite decades of policy attention and targeted interventions. Persistent under-representation at multiple career stages — from degree choices through senior academic and industry leadership — reflects a complex interplay of structural, cultural, and institutional barriers (Xie & Shauman, 2003; UNESCO, 2021). This article synthesises seminal explanations and recent empirical evidence to clarify the principal obstacles that limit women’s entry, retention, and advancement in STEM, and it outlines evidence-informed avenues for policy and institutional reform. (Xie & Shauman, 2003; Huang et al., 2020; UNESCO, 2021).
Historical and theoretical framing of barriers
Seminal sociological work situates gender differences in STEM within life-course and career-process frameworks: differential socialization, early achievement patterns, college major selection, family formation, and labour-market sorting jointly shape later career outcomes (Xie & Shauman, 2003). This model emphasises that simple “pipeline” metaphors obscure the multiplicity of transition points where women disproportionately leave STEM trajectories. In particular, family and household responsibilities, combined with occupational segregation and differential access to advanced training, produce long-term disparities in STEM career attainment (Xie & Shauman, 2003).
Recent large-scale bibliometric analyses corroborate and extend these theoretical claims by documenting persistent gender gaps in productivity, impact, and career length across countries and disciplines. Using publication records for over 1.5 million authors, Huang and colleagues (2020) demonstrate that gender differences in publication output and cumulative impact are robust and historically persistent, suggesting that structural forces — not merely short-term fluctuations — underpin observed disparities (Huang et al., 2020). These empirical patterns point to mechanisms such as differential collaboration networks, allocation of high-visibility tasks, and attrition at midcareer stages.
Structural and institutional barriers
Educational sorting and field segregation
Field segregation begins early: while women now approach parity or exceed men in many biological sciences, they remain under-represented in engineering, computer science, and physics. Educational choices reflect both preference formation and exposure to role models, curricula, and guidance; institutional curricula and gatekeeping practices (e.g., prerequisites, tracking) further channel students into gendered pathways (Xie & Shauman, 2003). UNESCO’s global monitoring confirms that women constitute a minority of tertiary graduates in engineering and computing and of professionals in emergent areas such as artificial intelligence, thus limiting the pool available for later leadership roles (UNESCO, 2021).
Hiring, evaluation, and the productivity penalty
Once in the workforce, women face institutional processes that operate to their disadvantage. Empirical work shows gendered differentials in hiring, grant success, and citation impact that cannot be fully explained by observable productivity metrics, reflecting biases in peer evaluation and networked advantage (Huang et al., 2020). Importantly, productivity measures themselves are shaped by unequal access to resources, mentorship, and high-status collaborations — creating feedback loops that amplify early disadvantages into long-term career differences (Huang et al., 2020).
Workplace culture, harassment, and exclusionary climates
Cultural climates within STEM workplaces — including tolerance of exclusionary norms, microaggressions, and sexual harassment — erode retention and advancement. UNESCO (2021) and related institutional reports note that hostile or unwelcoming environments discourage women from persisting in technical and research careers, and that such climates disproportionately affect early-career researchers and women from underrepresented backgrounds (UNESCO, 2021). These interpersonal and cultural factors interact with formal policies to produce tangible attrition.
Societal and familial constraints
Care responsibilities and the “motherhood penalty”
Caregiving responsibilities continue to fall unevenly on women in many societies, producing career interruptions and part-time employment that reduce cumulative productivity and slow promotion trajectories. Xie and Shauman (2003) detail how marriage and parenthood produce measurable divergences in career outcomes, particularly when institutional supports (childcare, parental leave) are absent or inadequate. The compounded effect of career breaks and reduced research time helps explain part of the gender gap in senior positions.
Stereotypes, identity, and self-selection
Cultural stereotypes about who “belongs” in STEM influence self-efficacy, identity formation, and choices long before entry into tertiary education. Stereotype internalisation reduces the likelihood that capable girls will pursue or persist in STEM majors (Xie & Shauman, 2003). Moreover, the lack of visible role models in particular subfields perpetuates the perception of STEM as gendered, creating a cyclical barrier to diversification.
Intersectionality and global variation
Barriers to participation are not experienced uniformly: race, socioeconomic status, nationality, and institutional prestige intersect with gender to shape distinct patterns of advantage and disadvantage. Huang et al. (2020) demonstrate heterogeneity across countries and disciplines, indicating that policy solutions must be sensitive to local labour markets, funding ecosystems, and cultural norms. UNESCO’s global synthesis likewise emphasises that low- and middle-income countries confront distinct structural constraints, including limited research capacity and resources, which interact with gendered norms to shape participation rates (UNESCO, 2021).
Evidence-informed interventions
Early-stage interventions: education and role models
Addressing field segregation requires interventions at the pre-college and undergraduate stages: curriculum reforms that broaden participation, outreach that demystifies technical careers, and visible role modelling can shift preferences and perceived identity congruence. Longitudinal evidence supports targeted mentoring and curriculum exposure as cost-effective ways to increase female enrolment in under-represented majors (Xie & Shauman, 2003).
Institutional reforms: hiring, evaluation, and support structures
At the institutional level, reforms that mitigate evaluative bias and support career continuity are essential. Examples include anonymised review where feasible, structured evaluation criteria, equivalent recognition of team and service contributions, transparent promotion pathways, and robust parental-leave and childcare support. Because productivity metrics are shaped by resource access and networked opportunities, policy must couple fairness in evaluation with equitable resource allocation (Huang et al., 2020).
Cultural change and accountability
Changing workplace culture requires sustained leadership commitment, measurable targets, and mechanisms for reporting and redress of harassment and discrimination. UNESCO (2021) emphasises the role of national and institutional accountability frameworks in shifting norms and creating safer, more inclusive environments for women in research and technology sectors (UNESCO, 2021).
Conclusion
Barriers to women’s participation in STEM are multifaceted, enduring, and mutually reinforcing. Seminal sociological analyses emphasise career processes and life-course mechanisms (Xie & Shauman, 2003), while comprehensive bibliometric studies document persistent differences in productivity and impact that reflect institutionalised inequalities (Huang et al., 2020). Global assessments underline that field segregation, hostile work climates, and uneven caregiving burdens all play central roles (UNESCO, 2021). Effective redress therefore requires a layered strategy: early educational reforms to broaden the talent pool; institutional policies to reduce bias and support continuity; and cultural interventions that address exclusionary norms. Combining rigorous evaluation with sustained political and organisational will offers the best prospect for transforming STEM into a genuinely inclusive enterprise.
References
Huang, J., Gates, A. J., Sinatra, R., & Barabási, A.-L. (2020). Historical comparison of gender inequality in scientific careers across countries and disciplines. Proceedings of the National Academy of Sciences of the United States of America, 117(9), 4609–4616.
UNESCO. (2021). UNESCO Science Report: The race against time for smarter development. UNESCO Publishing. ISBN 9789231004506.
Xie, Y., & Shauman, K. A. (2003). Women in science: Career processes and outcomes. Harvard University Press.
