Community violence and pregnancy: An understudied exposure in the etiology of adverse birth outcomes

Understanding the etiology of adverse birth outcomes is of critical public health importance. Preterm delivery and small-for-gestational age births are especially problematic because infants with these conditions experience heightened risk for serious morbidities, mortality, and poorer health and economic outcomes over the life course. There is stark patterning by race/ethnicity and socioeconomic position in the prevalence of adverse birth outcomes, but individual-level risk factors have not adequately explained these disparities. Researchers therefore have expanded their focus upstream to potential fundamental causes like neighborhood poverty and structural racism. However, given that these causes do not necessarily map to realistic interventions, researchers have sought to find a middle ground between fundamental and proximal causes, where the links between levels of causation are clearly articulated, to acknowledge the source of the inequities, but to also identify plausible policy or clinical interventions that could reduce disparities in maternal and infant health. This dissertation contributes to this literature by examining the role of community violence in the etiology of adverse pregnancy outcomes and the perpetuation of inequities in reproductive health. Community violence is a social exposure that is associated with neighborhood and individual socioeconomic status, factors that have been linked to adverse birth outcomes around the world. In addition, Black women in the United States are disproportionately likely to experience both community violence and poor pregnancy outcomes; therefore, community violence may be an important factor for understanding disparities in reproductive health outcomes by race/ethnicity. Furthermore, given that violence in a community is often tied to histories of racial/ethnic segregation, economic exclusion, and social marginalization, exposure to community violence may be an important mechanism through which historical patterns of social inequity continue to shape health disparities today. The first chapter of this dissertation provides background on this question and details potential pathways that could connect community violence with pregnancy outcomes. The second chapter addresses how exposure to homicide in one's neighborhood during early pregnancy influences risk of preterm delivery and small-for-gestational-age birth. The third chapter examines whether overall levels of firearm violence in a woman's community impact her risk of pregnancy complications and health behaviors during pregnancy and subsequent preterm birth. This work aims to assess the relationship between these factors, and to explore how they may be operating to produce disparities in preterm birth. The fourth chapter examines the relationship between exposure to fatal police violence during pregnancy on the hazard of early and late preterm delivery, and assesses whether there is effect modification by race/ethnicity. This chapter also addresses the fact that exposure to violence-related stress during pregnancy may be associated with an increased risk of spontaneous or induced abortion, and includes a simulation study to explore how using birth records that exclude these conceptions may affect the findings. The fifth chapter concludes. Overall, this work contributes new evidence about the relationship between community violence and adverse pregnancy outcomes, and improves our understanding of the etiology of inequities in reproductive health