Association Between Neighborhood Social Determinants of Health and Stillbirth

To examine the association between neighborhood-level social determinants of health and stillbirth.

We performed a retrospective cohort study of deliveries that occurred at a gestational age of at least 20 weeks within a five-hospital system (2012-2022). Electronic health record data mapped to the Observational Medical Outcomes Partnership Common Data Model were geocoded using addresses at the time of delivery and linked to neighborhood health indices, which included the Area Deprivation Index (ADI), Maternal Vulnerability Index (MVI), and Social Vulnerability Index (SVI) at the Census tract level. Stillbirths were adjudicated by medical record review. Modified Poisson regression generated relative risks (RRs) and 95% CIs, controlling for maternal age, body mass index (BMI), parity, marital status, chronic hypertension, and pregestational diabetes.

Among 61,008 pregnancies, 288 (0.5%, 95% CI, 0.4-0.5%) resulted in stillbirths. The ADI quartiles (relative to Census tracts within the United States as a whole) 2, 3, and 4 were associated with an increased risk of stillbirth (RR [95% CI] 2.32 [1.34-4.03], 3.08 [1.74-5.44], and 2.07 [1.03-4.14], respectively) compared with quartile 1. The ADI relative to Census tracts within the states showed comparable gradients. MVI quartiles 2 and 3 were associated with an increased risk of stillbirth (RR [95% CI] 1.44 [1.01-2.05] and 1.49 [1.02-2.19], respectively) compared with quartile 1. Similarly, SVI quartiles 2 and 3 were associated with an increased risk of stillbirth (RR [95% CI] 1.46 [1.03-2.07] and 1.86 [1.32-2.63], respectively) compared with quartile 1. Neither MVI nor SVI quartile 4 showed a statistically significant association with stillbirth. Among MVI subthemes, the mental health domain demonstrated a strong association with stillbirth (quartiles 2-4 RR range 1.64-2.07).

Neighborhood deprivation, quantified by ADI score, was a robust independent predictor of stillbirth, whereas the associations between the MVI or SVI and stillbirth were modest. Integrating the ADI into obstetric risk assessment and directing resources, especially perinatal mental health services, to highly deprived areas may help reduce persistent stillbirth disparities.