Environmental variables as potential modifiable risk factors of preterm birth in Philadelphia, PA.

OBJECTIVE: To examine whether variation in neighborhood context is associated with preterm birth (PTB) outcomes and gestational age (GA) at delivery in Philadelphia, and to determine whether these associations might persist when considering relevant individual-level variables. STUDY DESIGN: We analyzed individual-level data collected for a prospective cohort study of singleton pregnancies with preterm labor. We merged block-group level data to each individual's home address. Unadjusted analyses were performed to determine the association between block-group variables and individual-level outcomes. Block-group variables identified as potential risk factors were incorporated into multivariable individual-level models to determine significance. RESULTS: We analyzed data for 817 women. The prevalence of PTB < 37 weeks was 41.5%. Although in unadjusted analyses several block-group variables were associated with PTB and GA at delivery, none retained significance in individual-level multivariable models. CONCLUSION: Block-group level data were not associated with PTB outcomes or GA at delivery in Philadelphia.