Poor health at birth has negative long-run effects on individual well-being and is also detrimental for intergenerational mobility. This paper examines whether health outcomes at birth are affected by in utero increased exposure to rainfall and temperature shocks in Colombia, one of the countries in the world with the highest incidence of extreme weather events per year. The paper uses a fixed effects design to gauge the causal effect using variation in fetal exposure to these shocks by municipality and date of birth. The analysis finds negative effects of temperature shocks on birth health outcomes and no effect of rainfall shocks. The results indicate that heat waves lead to a 0.5 percentage point reduction in the probability of being born at full term and a decline of 0.4 percentage point in the probability of newborns classified as healthy. The timing of exposure to the shock matters and it matters differently for different outcomes. These findings are critical to prioritize responses to counteract the negative effects of weather, particularly hot shocks, which are projected to become more frequent and intense with changing climate.