Associations between Individual- and Structural-Level Racism and Gestational Age at Birth in the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be

The purpose of this study was to investigate the associations between multilevel racism and gestational age at birth among nulliparous women. We conducted a secondary analysis of data of the nuMoM2b Study (2010-2013) to examine the associations between individual- and structural-level experiences of racism and discrimination and gestational age at birth among nulliparous women (n = 9148) at eight sites across the U.S. Measures included the individual Experiences of Discrimination (EOD) scale and the Index of Concentration at the Extremes (ICE) to measure structural racism. After adjustment, we observed a significant individual and structural racism interaction on gestational length (p = 0.012). In subgroup analyses, we found that among those with high EOD scores, women who were from households concentrated in the more privileged group had significantly longer gestations (beta = 1.27, 95% CI: 0.48, 2.06). Women who reported higher EOD scores and more economic privilege had longer gestations, demonstrating the moderating effect of ICE as a measure of structural racism. In conclusion, ICE may represent a modifiable factor in the prevention of adverse birth outcomes in nulliparas.