  We present a large-scale bibliometric analysis of gender differences in
scientific careers, covering all scientific disciplines and a large number of
countries worldwide. We take a longitudinal perspective in which we trace the
publication careers of almost six million male and female researchers in the
period 1996-2018. Our analysis reveals an increasing trend in the percentage of
women starting a career as publishing researcher, from 33% in 2000 to about 40%
in recent years. Looking at cohorts of male and female researchers that started
their publication career in the same year, we find that women seem to be
somewhat less likely to continue their career as publishing researcher than
men, but the difference is small. We also observe that men produce on average
between 15% and 20% more publications than women. Moreover, in biomedical
disciplines, men are about 25% more likely than women to be last author of a
publication, suggesting that men tend to have more senior roles than women.
Compared with cross-sectional studies, our longitudinal analysis has the
advantage of providing a more in-depth understanding of gender imbalances among
authors of scientific publications.
