Association of Area Deprivation Index with perinatal and COVID-19 outcomes during the early pandemic: a secondary analysis of a prospective cohort study

Objective: We sought to evaluate the relationship between neighborhood-level deprivation and perinatal outcomes, particularly preterm birth, as well as COVID-19 outcomes among pregnant patients during the early pandemic. Methods: We performed a secondary analysis of a prospective longitudinal cohort study that investigated the impact of prenatal COVID-19 exposure on perinatal outcomes. Pregnant patients were recruited 12/23/20–7/18/22 and serially assessed for COVID-19 exposure during pregnancy, with serum antibody testing, electronic medical record review, and patient report. For this secondary analysis, address at the time of delivery was used to categorize patients into low ADI (≤50^th percentile Area Deprivation Index, indicating low level of deprivation) and highest ADI (≥75^th percentile, indicating highest level of deprivation) groups. The primary outcome was preterm birth, at <37 weeks, <34 weeks, and <28 weeks; secondary outcomes included other perinatal complications as well as COVID-19 outcomes. To further evaluate the effect of SARS-CoV-2 infection on pregnancy outcomes, we completed a subgroup analysis evaluating perinatal outcomes among patients who were SARS-CoV-2-positive at any point in pregnancy. Finally, we stratified patients by race to determine whether racism further impacted outcomes of SARS-CoV-2 infection, preterm birth, and gestational age at delivery. Results: 306 patients were included: 124 in the low ADI group and 182 in the highest ADI group. Baseline characteristics differed between groups, including notably lower rates of COVID-19 vaccination in the highest ADI group (24.2% vs 54.0%, p < 0.01). Overall, preterm birth rates did not differ between highest and low ADI groups (23.1% vs 17.7%, respectively, p = 0.26); however, highest ADI was significantly associated with higher rates of preterm birth before 28 weeks (12.1% vs 4.0%, p = 0.01) and before 34 weeks (12.6% vs 5.7%, p = 0.04) even after adjusting for obesity and tobacco use (<28 weeks aOR 0.26, 95% CI 0.07–0.73; <34 weeks aOR 0.35 95% CI 95% 0.14–0.87). The highest ADI group was more likely to develop SARS-CoV-2 infection (59.3% vs 41.9% p < 0.01), and more likely to be hospitalized due to COVID-19 (3.9% vs 0.0%, p = 0.04). In a subgroup analysis of patients who were SARS-CoV-2-positive during pregnancy, there were no differences found between ADI groups. After stratification by race, there were no statistically significant differences in SARS-CoV-2 infection rates, average gestational age at delivery, or preterm delivery rates between highest and low ADI groups for any race. Conclusion: Patients in the highest ADI group, therefore living in the most deprived neighborhoods, were more likely to experience extremely preterm birth, contract SARS-CoV-2 infection, and become hospitalized due to COVID-19. The interplay of social determinants of health and perinatal outcomes must be better studied to target interventions to modifiable risk factors.