RESUMEN
BACKGROUND: Short interpregnancy interval has been shown to be a key contributor to infant mortality. Black pregnant people have a higher incidence of short interpregnancy interval than people of other races and ethnicities, as well as higher rates of infant mortality. Understanding the factors related to racial disparities in short interpregnancy interval and infant mortality are a public health priority. OBJECTIVE: This study aimed to examine the relationship between social determinants of health and interpregnancy interval in Black pregnant people by comparing those with a short interpregnancy interval defined as <18 months with those with a referent interpregnancy interval defined as ≥18 months. STUDY DESIGN: This was a nested case-control study from a prospective cohort analyzing social determinants of health in 576 postpartum patients at an urban medical center, 2011-2021. Sociodemographic, pregnancy, and maternal characteristic data were collected from participants' medical records. Structured interviews measured participants' health behaviors, physical environment, social support, health literacy, and structural drivers. Differences in social determinants of health among Black study participants were compared between those with a short interpregnancy interval (<18 months) and those with a referent interpregnancy interval (≥18 months). The odds ratios were calculated to assess the association between short interpregnancy interval and social determinants. Factors with significant differences between the short interpregnancy interval and referent interpregnancy interval groups in Black participants were compared with that of White groups for social context. RESULTS: Black participants with a short interpregnancy interval were more likely to report financial support from the Special Supplemental Nutrition Program for Women, Infants, and Children (odds ratio, 2.4; 95% confidence interval, 1.2-5.1), negative feelings toward the pregnancy (odds ratio, 2.4; 95% confidence interval, 1.2-4.9), choosing not to breastfeed because they do not like it (odds ratio ,12.0; 95% confidence interval, 1.5-543.1), not receiving prenatal care as early as desired (odds ratio, 3.4; 95% confidence interval, 1.6-7.2) because of consid- eration of pregnancy termination (odds ratio, 5.2; 95% confidence interval, 1.2-30.5) and less likely to report low levels of social support (odds ratio, 0.3; 95% confidence interval, 0.1-0.8) than Black participants with a referent interpregnancy interval. CONCLUSION: Social determinants of health that differed between participants with a short interpregnancy interval and those with a referent interpregnancy interval were Special Supplemental Nutrition Program for Women, Infants, and Children support, feelings toward the pregnancy, social support, breastfeeding intent, and delayed prenatal care because of consideration of abortion. Previous studies examining infant mortality risk factors used White people as the referent group when analyzing social determinants. Our study focused specifically on understanding the lives of Black pregnant people so that future public health initiatives focused on social determinants may attenuate the racial disparity of infant mortality in the United States.
