This study examines the impact of the Orion Operation on newborn health outcomes. Previous research has explored the negative effects of conflict on child health, but the specific consequences of state military operations on newborns, especially in urban settings, remain poorly understood. Employing a Difference-in-Differences design and using administrative data from the Colombian Vital Statistics Reports, we assess the effects of the Orion Operation on birth weight, height, and the probability of a high Apgar score. Our analysis reveals a significant reduction in birth weight among infants born in intervention-affected neighborhoods, with concentrated effects observed among married and less educated mothers. We find a decrease in height at birth and a reduction in the probability of having an Apgar score higher than 7, which indicates good health at birth. While direct testing of stress as the primary underlying mechanism was unfeasible, our findings suggest that stress might influence birth outcomes. These findings enhance our understanding of the complex impacts of state military operations and underscore the importance of considering the context when assessing their consequences on local communities.