(692) Impact of Social Vulnerability Index (SVI) on Nulliparous Term Singleton Vertex (NTSV) Cesarean Delivery Rate

Objective: To determine if Social Vulnerability Index (SVI) is associated with incidence of Nulliparous, Term, Singleton, Vertex (NTSV) cesarean deliveries (CD). We hypothesized that patients living in more socially vulnerable areas (increased SVI) would have a higher CD rate.

Study Design: Multicenter retrospective cohort of NTSV patients who delivered at one of seven hospitals in a large academic health system from 2019-2021. Patient addresses were used to identify census tracts, which were then linked to SVI scores. SVI is a tool released by the Centers for Disease Control and Prevention (CDC) that incorporates data from U.S. Census Bureau on socioeconomic status, household composition, minority status, and housing/transportation. Baseline demographic data was obtained from the electronic medical record system and compared between SVI quarters (0-0.25, 0.26-0.50, 0.51-0.75, 0.76-1.0). Logistic regression was used to model the probability as a function of SVI while adjusting for race-ethnicity, maternal age, BMI category, health insurance type, language, induction or augmentation of labor, and hospital location.

Results: 26,219 deliveries were included in the study. The NTSV CD rate was 28.9% (n = 7579). Table 1 shows the demographic distribution across SVI quarters. On unadjusted analysis, there was a negative association between SVI and CD, with every 1 unit increase in SVI quarter associated with a 5% greater likelihood of vaginal delivery (OR 0.95, 95% CI 0.93-0.97). However, adjusted analysis suggested significant interaction between SVI and race/ethnicity (p=0.016). After adjusting the model for the race/ethnicity interaction, no evidence of an association between SVI and CD (p=0.23) was observed.

Conclusion: SVI does not significantly affect the NTSV CD rate. This finding is contrary to our hypothesis and suggests that local neighborhood socioeconomic characteristics do not impact obstetric delivery outcomes.