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

INTRODUCTION: 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). METHODS: 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. RESULTS: 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). CONCLUSION: 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.