Impact of gender on the formation and outcome of mentoring relationships in academic research

An imbalance in gender representation has been identified across many fields of academic research. Men are disproportionately represented, especially at senior career stages. Efforts to increase recruitment of women into training programs has increased representation in many fields, but a "leaky pipeline" is still observed: a disproportionate number of women leave research before obtaining an independent position. To understand factors that lead to attrition of women from academic research, we analyzed a database of mentoring relationships covering the period 2000 to 2015 in several science and humanities fields. While representation of women has increased over time among both trainees and independent researchers, male graduate students and postdocs still continue to independent research at higher rates than their women colleagues. We analyzed aspects of the mentoring relationship that contribute to this continuing bias. One strong pattern that is observed is homophily, where trainees and mentors tend to be of the same gender. It has been hypothesized that institutional bias may limit the influence of female investigators, which could in turn impact the retention of their trainees in academia. Indeed, we observe trainees of female mentors are less likely to continue into independent research careers than trainees of male mentors. This disparity persists, but is reduced, after controlling for temporal trends in retention rates and under-representation of women mentors at the highest levels of funding and citation. Although the trainee pool for mentors that receive highly prestigious awards is skewed towards men, homophily is otherwise unrelated to mentor achievement. These results suggest that, in addition to other factors that limit career choices for female trainees, institutional bias that gives female mentors access to fewer resources contributes to the leaky pipeline for gender.