Background: In the United States, Black women experience preterm birth (PTB; <37 weeks gestation) at more than 1.5 times the rate of non-Hispanic White women. Social determinants of health including the neighborhood environment have been recognized as contributing to the risk of PTB. Due to historical segregation, Black women are more likely to live in neighborhoods with higher levels of neighborhood disorder compared with White women. Perceived neighborhood disorder appears to be a risk factor for maternal psychological distress in Black women and psychological distress has mediated the association between neighborhood disorder and the risk for PTB. However, the biological pathways underpinning these associations are not clear. Objective: We examined the associations among neighborhood disorder; psychological distress; DNA methylation of six stress-related, glucocorticoid candidate genes (AVP, CRH, CRHBP, FKBP5, HSD11B2, NR3C1); and gestational age at birth among 44 Black pregnant women. Methods: Women who were 18-45 years old and 8-18 weeks gestation had blood drawn and completed questionnaires measuring perceived neighborhood disorder, neighborhood crime, and psychological distress. Results: Three CpG sites were associated with neighborhood disorder (cg03405789 [CRH], cg14939152 and cg15910486 [NR3C1]). One CpG site, cg03098337 (FKBP5) was associated with psychological distress. Three of the identified CpG sites were located within gene CpG islands or shores-areas at which DNA methylation is known to affect gene transcription. Conclusion: These findings warrant further research to clarify intermediate biological pathways and potential biomarkers to identify women at risk for PTB. Identification of PTB risk early in pregnancy would allow for interventions to prevent PTB.
Keywords: DNA methylation; Preterm birth; neighborhood; prematurity; psychological stress.