Social vulnerability and cervical length surveillance in patients at increased risk for spontaneous preterm birth

We aimed to evaluate the association between the social vulnerability index (SVI) and cervical length (CL) surveillance in patients at increased risk for spontaneous preterm birth (sPTB). Retrospective cohort study of all patients who had 2 or more CLs between 16 0/7 and 23 6/7 weeks’ gestation within a university health system from 1/1/19 to 12/31/21. Patient home addresses were used to identify census tracts and these were then linked to SVI scores released by the Centers for Disease Control and Prevention. Patients with multiple gestations and missing SVI and outcome data were excluded. Subsequent deliveries that occurred during the study period for the same patient were also excluded. The cohort was stratified into 4 groups based on SVI percentile ranking: quarter 1 (Q1, 0-0.24), Q2 (0.25-0.49), Q3 (0.50-0.74), Q4 (0.75-1.0). Maternal and pregnancy characteristics were compared among the 4 groups using Chi-squared test and analysis of variance with statistical significance set at P < 0.05. 2,108 patients were included. The majority of CL surveillance occurred in patients within the lower 2 SVI Qs (1,240/2,108, 58.8%). The prevalence of younger patients, Non-Hispanic black and Hispanic race/ethnicity, public insurance, history of preterm birth, and a short cervix (CL ≤ 2.5mm) in this pregnancy was significantly increased in the higher SVI Qs compared to the lower SVI Qs (Table 1). PTB prior to 37 weeks’ gestation was also significantly increased in the higher SVI Qs compared to the lower SVI Qs, while PTB prior to 34 weeks’ gestation was similar among the four groups (Table 2). The majority of CL surveillance in our population occurred in patients with a lower SVI score. Nevertheless, PTB rates were highest among those with a higher SVI score, which also included a disproportionately higher prevalence of risk factors associated with sPTB.View Large Image Figure ViewerDownload Hi-res image Download (PPT)