Effects of a natural experiment on maternal and infant health - PROJECT SUMMARY Rates of adverse maternal and infant health outcomes (e.g., preterm delivery, severe maternal morbidity, and mortality) in the United States (US) substantially outpace other high-income nations and are unacceptably high among women identifying as Black, American Indian, or Alaska Native and those living in rural areas. Municipalities and states across the US have begun implementing cash transfer programs, many targeted to pregnant women or families, with the objective of improving maternal and infant health through poverty reduction. Yet, evidence about the impact of cash transfers (i.e., intentional monetary transfers to individuals or households) on maternal and infant health in the US is decidedly mixed. A temporary expansion of the US Child Tax Credit (CTC) that led to an unprecedented 35% reduction in child poverty in 2021 offers an ideal natural experiment with which to test the impact of receiving monthly cash transfers during pregnancy on maternal and infant health. Surprisingly, our own preliminary ecological study indicated that the 2021 CTC expansion preceded an unexpected increase in low birth weight (LBW) among births to women likely to have received the CTC.17 This work calls into question the straightforward assumption that cash transfers in the US (such as the CTC) would improve infant health. The overall goal of this proposal is to thus examine the impact of cash transfers during pregnancy on maternal and infant health and health disparities in the US. The specific aims of this proposal are to 1) Estimate impacts of receiving CTC monthly payments during pregnancy on maternal and infant health, and 2) Determine whether impacts of receiving CTC monthly payments during pregnancy on maternal and infant health differ by race/ethnicity, socioeconomic status, or rurality. Exploiting, as a natural experiment, the unexpected and temporary monthly CTC payments received by ~40% of pregnant women between July and December of 2021, we will construct a simulated instrument to estimate individual-level impacts of the CTC expansion during pregnancy on maternal and infant health, and we will use rigorous methods to account for other health, social, policy, and economic changes during the COVID-19 pandemic. We will use two high-quality survey and administrative datasets (i.e., US Natality data and the Pregnancy Risk Assessment Monitoring System survey) to assess maternal and infant health measures plausibly impacted by cash transfers. Our study team, with 15 years of collaboration and expertise in maternal health, impacts of cash transfers on health, and the proposed methods and datasets, is ideally poised to achieve our goal. Our proposal responds directly to an NICHD Notice of Special Interest. Achieving these aims will increase understanding of how cash transfers impact maternal and infant health and will inform development of ongoing programs and policies, including local cash transfer pilot projects and future changes to the CTC and other tax credits.