Understanding weather, climate, and birthweight: Findings from the U.S. natility data files 1969–78

Weather and extreme weather events are thought to be related to low birth weight. If this relation is held, it will have a wide range of public health impacts as birth weight is a key indicator of many life course health outcomes, and climate change increases the intensity of extreme weather events. The current study examines the relationship between birth weight and weather variables during the birth month while controlling other known risk factors. While the preliminary results seem to suggest a relationship between birth weight and extreme hot temperature, the result does not hold when individual and other risk factors are introduced. It is concluded that birth weight is primarily related to the temperature of birth month: the colder the month, the heavier the baby, to some degree. Even though we did not confirm the relationship between birth weight and extreme weather events, global warming is still likely to negatively affect birth outcomes.