For a study, researchers sought to determine the extent to which neighborhood variables contribute to racial and ethnic inequalities in SARS coronavirus 2 (SARS-CoV-2) seropositivity in pregnancy. From April 13 through December 31, 2020, pregnant women who arrived for deliveries at two hospitals in Philadelphia, Pennsylvania, were included in this cohort research. SARS-CoV-2 seropositivity was assessed by quantifying immunoglobulin G and immunoglobulin M antibodies in discarded maternal serum samples acquired for clinical reasons using an enzyme-linked immunosorbent assay. Self-reported race and ethnicity were extracted from medical records. The addresses of patients were geocoded to get three Census tract variables: community deprivation, racial segregation (Index of Concentration at the Extremes), and crowding. Mixed-effects with several variables To quantify the extent to which neighborhood characteristics may explain racial and ethnic inequalities in seropositivity, logistic regression models and causal mediation analyses were performed.

About 562 (9.4%) of 5,991 pregnant patients tested positive for SARS-CoV-2. Hispanic (19.3%, 104/538) and Black (14.0%, 373/2,658) patients had higher seropositivity rates than Asian (3.2%, 13/406) patients, White (2.7%, 57/2,133) patients, and patients of another race or ethnicity (5.9%, 15/256) patients (P<.001). Per SD increase, deprivation (aOR 1.16, 95% CI 1.02–1.32), and crowding (aOR 1.15, 95% CI 1.05–1.26) were linked with seropositivity in adjusted models, while segregation was not (aOR 0.90, 95% CI 0.78–1.04). According to mediation analyses, crowded housing may explain 6.7% (95% CI 2.0–14.7%) of the Hispanic–White discrepancy, while neighborhood deprivation may explain 10.2% (95% CI 0.5–21.1%) of the Black-White disparity. In the prevaccination era, neighborhood poor and crowding were related to SARS-CoV-2 seropositivity in pregnancy, which may help to explain the high prevalence of SARS-CoV-2 seropositivity among Black and Hispanic patients. Investing in structural community improvements may help to lessen viral transmission disparities.