Association of Reproductive Autonomy and Rates of State-Level Racialized Disparities in Preterm Birth and Low Birthweight.

Abstract

Reproductive policies' impact on disparities in neonatal outcomes is understudied. Thus, we aimed to assess whether an index of reproductive autonomy is associated with black-white disparities in preterm birth (PTB) and low birthweight (LBW). We used publicly available state-level PTB and LBW data for all live-births among persons aged 15-44 from January 1, 2016, to December 31, 2018. The independent measure was an index of state laws characterizing each state's reproductive autonomy, ranging from 5 (most restrictive) to 43 (most enabling), used continuously and as quartiles. Linear regression was performed to evaluate the association between both the index score (continuous, primary analysis; quartiles, secondary analysis) and state-level aggregated black-white disparity rates in PTB and LBW per 100 live births. Among 10,297,437 black (n=1,829,051 [17.8%]) and white (n=8,468,386 [82.2%]) births, rates of PTB and LBW were 6.46 and 8.24 per 100, respectively. Regression models found that every 1-U increase in the index was associated with a -0.06 (confidence interval [CI]: -0.10 to -0.01) and -0.05 (CI: -0.08, to -0.01) per 100 lower black-white disparity in PTB and LBW rates (p<0.05, p<0.01), respectively. The most enabling quartiles were associated with -1.21 (CI: -2.38 to -0.05) and -1.62 (CI: -2.89 to -0.35) per 100 lower rates of the black-white disparity in LBW, compared with the most restrictive quartile (both p<0.05). Greater reproductive autonomy is associated with lower rates of state-level disparities in PTB and LBW. More research is needed to better understand the importance of state laws in shaping racialized disparities, reproductive autonomy, and birth outcomes.