Heatwaves and delivery practices: The effects of extreme temperature in Brazilian maternity wards

This paper examines how extreme heat affects healthcare delivery, using data on around 25 million births in Brazilian public hospitals between 2008 and 2019. Combining satellite-based temperature records with a high-dimensional fixed-effects design, we study how delivery practices and provider allocation vary with short-run temperature fluctuations in maternity wards. We find that extreme heat is associated with a lower probability that deliveries are led by physicians and a corresponding increase in nurse-led births, alongside a decline in cesarean section rates. Among physician-attended deliveries, extremely hot days are associated with a higher likelihood of pre-labor cesarean sections, consistent with shifts toward faster procedures under thermal stress. We find no detectable effects on immediate neonatal health as measured by Apgar scores. Together, these results suggest that temperature shocks reshape clinical decision-making and task allocation in maternity wards, revealing an operational channel through which climate stress affects healthcare delivery.