Effects of a federal smoke-free housing policy on adverse birth outcomes among NYC public-housing residents.

Introduction: Identifying strategies to mitigate the effects of secondhand smoke exposure is crucial for public health. Thus, we estimated the effect of a 2018 federal smoke-free housing (SFH) policy on adverse birth outcomes among New York City (NYC) public-housing residents.

Methods: We obtained data on all live births to NYC residents in NYC from 2013 to 2022, using the borough-block-lot of the birthing person's address to identify births to public-housing residents. We then estimated the effect of the SFH policy on risk of preterm birth or low birth weight among births to NYC public-housing residents using a linear-probability difference-in-differences estimator, weighted by inverse probability weights to increase the plausibility of the parallel-trends assumption.

Results: Our sample included 44 455 births to public-housing residents and 803 648 births to non-public-housing residents. Difference-in-difference analyses suggested the SFH policy did not affect risk of preterm birth (risk difference (RD) per 100: 0.1; 95% CI -0.6 to 0.9) or low birth weight (RD per 100: 0.3, 95% CI -0.4 to 1.0). Event-study analyses supported these findings and lent credibility to the parallel-trends assumption.

Conclusions: We estimated no initial effects of a federal SFH policy on risk of preterm birth or low birth weight among births to NYC public-housing residents.