(WITHDRAWN) Examining the Social Determinants of Health and Preterm Birth: Moderation By Gestational Hypertension

Background and Purpose: Adverse pregnancy outcomes, such as preterm birth, have been associated with preconception and prenatal risk factors, including hypertensive disorders of pregnancy (such as chronic hypertension, gestational hypertension, and preeclampsia). Receiving adequate prenatal care is key to manage and prevent adverse pregnancy outcomes. Despite prenatal care interventions, adverse pregnancy outcomes are still high, especially among women with hypertensive disorders of pregnancy and non-Hispanic Black women. Evidence indicates that social determinants of health may create disparities in adverse pregnancy outcomes. For pregnant women with hypertensive disorders of pregnancy, it might be the effects of the social determinant of health that influenced these outcomes, especially for non-Hispanic Black women, because the evidence indicates the impact of social determinants of health outweighs healthcare and lifestyle choices. However, it is not yet known whether being hypertensive during pregnancy or a social determinant of health is associated with preterm birth. Therefore, the objective of this study is to examine social determinants of health as independent risk factors in predicting preterm birth in women with and without hypertensive disorders of pregnancy. Additionally, we will examine unique associations within specifical racial/ethnic groups.

Methods: Data were drawn from the Early Childhood Longitudinal Study- Birth Cohort, which is a nationally-representative and longitudinal study of children born in 2001. Preterm birth in weeks included a continuous measure of the number of weeks children were born prior to 37 weeks gestation. The social determinants of health included food insecurity, adequacy of prenatal care, maternal education, income-to-needs, maternal employment, and maternal substance use. The moderator was maternal hypertension and included a dichotomous indicator of whether mothers had chronic or gestational hypertension. First, linear regressions were estimated in which preterm birth was regressed on the social determinants of health. Second, multiple group analyses with linear regressions were estimated based on whether mothers did or did not report hypertension. The third set of models replicated models one and two, but within racial/ethnic groups.

Results: Compared to adequate prenatal care, inadequate prenatal care was associated with an increased risk of preterm birth (β = 0.04, p < .05). Higher income-to-needs was negatively associated with preterm birth (β = -0.03, p < .01). When examining multiple group models, the results remained consistent for mothers without hypertension. For mothers with hypertension, none of the social determinants for health were significantly associated with preterm birth. There were some differences in these associations based on maternal race/ethnicity.

Conclusions: Among the entire sample, adequacy of prenatal care and income-to-needs are important predictors of preterm birth. However, these effects are ameliorated for mothers with hypertension. The associations between social determinants of health and preterm birth were unique across racial/ethnic groups and hypertension status. Mothers with hypertension are a particularly vulnerable group that needs supports and resources to prevent preterm birth. Practice and policy need to consider both health status and racial/ethnic identity when tailoring supports.