(99) The Chicago Perinatal Origins of Disease Study: Exploring Associations Between Adverse Maternal Exposures and Gestational Age at Birth

Background: High psychosocial stress and hardship during pregnancy are associated with preterm birth. We sought to evaluate associations between maternal psychosocial environment in pregnancy with gestational age at birth (GA). We hypothesize that high psychosocial stress will be associated with earlier GA.

Objectives: To assess the impact of pre- and perinatal maternal exposure to social stress on GA.

Design/Methods: We conducted an interim analysis of the Chicago Perinatal Origins of Disease cohort, a longitudinal, observational study of pregnant people and their infants enrolled at two obstetric clinics in Chicago, IL. Participants reported residential address and completed validated survey instruments during second and third trimesters of pregnancy. Exposures of interest included Child Opportunity Index (COI), social support, psychosocial stress, and structural social determinants of health. COI was dichotomized to compare lowest quartile to all other quartiles; other measures were either dichotomized to high vs. low adverse exposure or continuous validated survey scores. The primary outcome was GA. Mann-Whitney U tests compared maternal exposures to GA. We evaluated effect size using linear regression models adjusted for maternal age.

Results: Among the total cohort of 213 enrolled participants, 156 had given birth and were included in this analysis (Table 1). Low perceived social support was associated with lower GA (p = 0.03). In adjusted regression models, low perceived social support remained significantly associated, and food insecurity was also found to be associated with lower GA (Table 2). Further, several other maternal exposures, such as COI and experiences of discrimination, trended towards a significant association with lower GA.

Conclusions: Insufficient maternal social support, food insecurity, and potentially other psychosocial exposures in pregnancy are associated with earlier GA. Infants that are born earlier are at higher risk of neonatal morbidity and intensive care unit admission compared to those born at later GA. Given the ongoing nature of this study, additional factors affecting GA may be elucidated with continued expansion and diversification of the cohort. Evaluation of maternal individual- and community-level factors contributing to adverse exposures during pregnancy is critical to inform targeted interventions addressing social hardship and support during the perinatal period.