We find that graduate mothers suffer penalties of 25 percentage points on their annual output of scientific publications compared to fathers in the first seven years after childbirth. Estimated motherhood penalties are even greater, at 40 percentage points, for researchers who are active in publishing prior to childbirth. At the same time, the impact of scientific contributions by publishing mothers is reduced after childbirth, despite unchanged publication quality, indicating that both knowledge creation and knowledge diffusion are hampered by motherhood. The largest productivity declines occur among early-career researchers and mothers in laboratory-intensive and clinical fields, which are incompatible with remote work. In contrast, support from a flexible partner and access to informal help significantly ease care-related constraints on women’s research performance.

This study investigates the unequal effects of parenthood on the scientific productivity of mothers and fathers in the natural sciences and medicine. Leveraging a unique combination of administrative registers and granular bibliometrics, our event study follows the individual research productivity of university graduates in Denmark across the birth of their first child, exploring constraints in their private and professional spheres, related to scientific fields, research responsibilities, sector of employment, and household characteristics.