Mixed effects cox model of wildfire smoke-day exposure during post-partum trimester at the 25% exposure threshold, in all eligible children and stratified by sex. P1 and P2 periods correspond to 0–12 and 13–24 weeks, respectively. Models are adjusted for birth-season, birthyear and, where applicable, sex, with a random intercept for MSA. All exposures are the average weekly number of smoke-days in the given post-partum period. RX = prescribed medication claim; “25% exposure threshold” refers to population-weighted percentage of zip codes, here 25%, within an MSA required to experience a smoke-day, in order to assign a smoke-day to the MSA