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Pipelines are not meant for people

The Leaky Pipeline metaphor does a huge disservice to the vast majority of STEMM graduates who donot become professors. Here’s a more realistic picture:

The Leaky Pipeline metaphor provides a compelling graphic for the underrepresentation of women in faculty positions. Sometimes referred to as a ‘scissors diagram’, these graphics generally show a stark contrast in the representation of women up to the postdoctoral level (where they are at parity with men in most fields) with their representation at the level of tenured faculty. Such underrepresentation is a valid and serious concern for universities and research institutes especially given recent findings that link innovation and novelty of research with the diversity of research teams [1]. Despite this valid motivation and the accuracy of the numbers, the data that support the Leaky Pipeline metaphor are misleading and unfair to individuals who have pursued degrees in STEMM (science, technology, engineering, mathematics, and medicine). It is thus unsurprising that this metaphor has failed to generate solutions to the underlying problem of women’s underrepresentation at the tenured faculty level. 

The underrepresentation of women at the faculty level is not a supply problem 

It is fundamentally inappropriate to compare the percentages of women at different levels in academia because the size and turnover of these pools are so different. As the graphic above shows, the pool of doctoral students and postdocs in biology (based on a 2012 NIH report [2]) is roughly 4-5 times as large as the pool of tenure-track and tenured faculty. Turnover, though harder to estimate, is likely around 3 times higher for the combined pool of doctoral students and postdocs than for faculty. Although these differences in turnover complicate the snapshot comparison of pool sizes, it is obvious that the vast majority of current and recent doctoral degree holders simply cannot be accommodated in faculty positions. While this is shown in the graphic for biology, the situation is similar in many (if not most) fields. There is a massive oversupply of doctoral degree holders (and even of the roughly half of them who are female) for these positions. 

STEMM doctoral students and postdocs deserve support for career development that does not target a faculty position 

Doctoral degree graduates have varied opportunities to make important contributions to society. Activities outside academia often have more profound impact on society and human welfare than can be achieved through an academic career. As a quick example, think of two women who obtained STEMM degrees before achieving the highest level of political leadership [3]. Such contributions should not be devalued because they do not match the experience and values of doctoral supervisors. Doctoral supervisors may benefit from a single-minded focus on a professorial position. But society suffers from the delay in the enthusiastic participation of STEMM doctoral degree holders in other career paths, and statistically, most doctoral graduates will feel disappointed to some extent if (or more likely, when) their careers do not lead to a faculty position. Doctoral students and postdocs, as well as students considering further education and training, would benefit from transparent information on the career paths pursued by peer groups at academic institutions. 

STEMM doctoral students and postdocs would benefit from broader exposure to non-academic career pathways 

Exposure to non-academic career paths could be expanded in many ways. Professional career development could involve contact with alumni who have pursued various career paths. Opportunities for short-term engagement outside academia could be provided. Non-academic sabbaticals could be encouraged both for faculty to gain experience in non-academic settings and for non-academic professionals to share their experience with doctoral students and postdocs during stays in academia. Such interactions across the boundary of academia could also lead to valuable cross-fertilization of ideas and the development of novel approaches to problem solving. 

STEMM careers (especially in academia) need to be more flexible and attractive 

The prevailing research culture in academia is widely viewed as inhumane, even toxic [4]. During the COVID 19 pandemic, it became abundantly clear that these pressures had a disproportionate impact on early career researchers and on women in positions of academic leadership (including professors) especially those with children or other care-giving responsibilities. These two groups share a common interest in reforming – or even transforming – the current academic system [5]. Their interests are not served by inflexibility of the academic career track (exemplified by the ‘pipeline’ metaphor). A transition away from the current incentive system in academic STEMM, which strengthens academic hierarchies by over-emphasizing the role of paternalistic team leaders and under-emphasizing the roles of team members, to a fairer and more diverse value system is needed [6]. This would lead to a healthier and more attractive environment with better supervision and more transparent career paths and, in all likelihood, to more creative and actionable research. 

Attention to STEMM education is needed before students enter the university 

There are a few STEMM fields, particularly information and computer technology, engineering, and physics, where women are severely underrepresented even at the undergraduate level. As Athene Donald explains in her book Not Just for the Boys: Why We Need More Women in Science , a variety of social pressures discourage girls from developing their capacity in mathematics and the physical sciences [7]. In these fields, there tends to be relatively little further drop-off in women’s representation between doctoral studies and higher levels in academia. Given the relative size and turnover of the pools, it would, of course, be entirely possible for the proportion of women to increase at least at the entry level for a faculty career. Reducing the exposure of girls and boys to stereotyped gender expectations would help to meet societies’ need for a scientifically and technical literate population. 


Childhood and early education. Combat societal pressures – from gender-specific toys to feedback from teachers – that discourage children and young adults from developing their full range of capacities. Actively encourage all children and young adults to develop their curiosity and engage them in the process of scientific discovery. 

Higher education – career development. Provide transparent and accessible statistics on entry and completion rates, pool sizes and turnover at various academic levels that is disaggregated by field of study. Provide information on career trajectories of doctoral degree holders and offer doctoral students and postdocs guidance on non-academic careers and relevant preparation for them. 

Higher education and research – work environment and incentives. Critically assess traditional expectations and incentives in academic research careers that are incompatible with caring responsibilities and mental health. Avoid perverse incentives that drive supervisors to prioritize academic careers for their doctoral students and postdocs. Increase recognition and rewards for teamwork. 

Janet Hering is Director Emerita of the Swiss Federal Institute of Aquatic Science & Technology (Eawag),Professor Emerita of Environmental Biogeochemistry at the Swiss Federal Institute of Technology, Zürich(ETHZ) and Professor Emerita of Environmental Chemistry at the Swiss Federal Institute of Technology,Lausanne (EPFL). She is a former Chairwoman of the ETH Women Professors Forum. 

This article expresses the personal opinion of the author and does not necessarily reflect the position of any institution or group with which she is affiliated. 


[1] Nielsen, M.W., Alegria, S., Börjeson, L., Etzkowitz, H., Falk-Krzesinski, H.J., Joshi, A., Leahey, E., Smith-Doerr, L., Woolley, A.W. and Schiebinger, L. (2017) Gender diversity leads to better science, PNAS , 114:1740-1742,

[3] Answers: Margaret Thatcher (Prime Minister of the United Kingdom, 1979-1990), Angela Merkel (Chancellor of Germany, 2005-2021) 

[4] Hall, S. (2023) A mental-health crisis is gripping science — toxic research culture is to blame, Nature 617: 666-668,

[5] Hering, J. G., Green, S. A., Heckmann, L., Katehi, L. P.B., Maurice, P. A. & Young, S. (2022). A call for an alliance between female academic leaders and early career researchers to improve the academic STEM system. Elephant in the Lab .

[6] Better Science Initiative, University of Berne,

[7] Donald, A. (2023) Not Just for the Boys: Why We Need More Women in Science , Oxford: Oxford University Press, 276 pp. 


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