title: Environmental variables as potential modifiable risk factors of preterm birth in Philadelphia, PA.
abstract: 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.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  Block-group level data were not associated with PTB outcomes or GA at delivery in Philadelphia.
authors.affiliation: Maternal and Child Health Research Program, Department of Obstetrics and Gynecology, Center for Research on Reproduction and Women's Health, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Electronic address: jbastek@obgyn.upenn.edu.
authors.forename: Jamie A
authors.initials: JA
authors.lastname: Bastek
authors.affiliation: Department of Biostatistics and Epidemiology, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Mary D
authors.initials: MD
authors.lastname: Sammel
authors.affiliation: Cartographic Modeling Lab, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Tara D
authors.initials: TD
authors.lastname: Jackson
authors.affiliation: Maternal and Child Health Research Program, Department of Obstetrics and Gynecology, Center for Research on Reproduction and Women's Health, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Meghan E
authors.initials: ME
authors.lastname: Ryan
authors.affiliation: Maternal and Child Health Research Program, Department of Obstetrics and Gynecology, Center for Research on Reproduction and Women's Health, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Meghan A
authors.initials: MA
authors.lastname: McShea
authors.affiliation: Maternal and Child Health Research Program, Department of Obstetrics and Gynecology, Center for Research on Reproduction and Women's Health, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Michal A
authors.initials: MA
authors.lastname: Elovitz
mesh_terms: D003415:Crime / Q000706:statistics & numerical data; D004777:Environment; D005260:Female; D006801:Humans; D007182:Income / Q000706:statistics & numerical data; D015143:Philadelphia; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology*; D011295:Prenatal Care / Q000706:statistics & numerical data; D011446:Prospective Studies; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D012307:Risk Factors; D012959:Socioeconomic Factors; D013223:Statistics as Topic
keywords: Philadelphia; census block-group; environment; preterm birth