Time to Spare and Too Much Care? Crowding, Medical Intervention and Health Outcomes in the Maternity Ward

This paper examines the causal effect of crowding in maternity wards on medical treatment and health outcomes. To address endogeneity concerns, I focus on mothers and their newborns in Norwegian maternity wards and use the number of women with the same due date in a local area as an instrument for crowding. Using detailed administrative data covering all births in Norway over multiple years, I find that crowding—measured as a higher admission level— causes fewer unplanned readmissions and improved APGAR scores. On crowded days, mothers receive fewer inductions and other medical interventions, and no corresponding increase in reported complications. The instrumental variable strategy addresses potential endogeneity biases inherent in fixed‐effects models and yields qualitatively similar estimates.