title: The benefit of preterm birth at tertiary care centers is related to gestational age.
abstract: OBJECTIVE
  The purpose of this study was to examine the relationship between gestational age and outcomes of outborn versus inborn preterm infants.
  
  
  METHODS
  Multivariable logistic regression analysis was used to examine gestational age-specific, risk-adjusted outcomes of 2962 singleton infants who were born at <32 weeks of gestation who were admitted to 17 Canadian neonatal intensive care units from 1996 through 1997.
  
  
  RESULTS
  The risk-adjusted incidence was significantly (P <.05) higher among outborn versus inborn infants for mortality rates (odds ratio, 2.2) and > or =grade 3 intraventricular hemorrhage (odds ratio, 2.1) at < or =26 weeks of gestation and for chronic lung disease (odds ratio, 1.7) at 27 to 29 weeks of gestation. Outcomes of outborn and inborn infants at 30 to 31 weeks of gestation were not significantly different.
  
  
  CONCLUSIONS
  The short-term benefit of preterm birth at tertiary centers is related inversely to gestational age and may not extend beyond 29 weeks of gestation.
authors.affiliation: Department of Pediatrics, University of British Columbia, Vancouver, Canada.
authors.forename: Shoo K
authors.initials: SK
authors.lastname: Lee
authors.forename: Douglas D
authors.initials: DD
authors.lastname: McMillan
authors.forename: Arne
authors.initials: A
authors.lastname: Ohlsson
authors.forename: Jill
authors.initials: J
authors.lastname: Boulton
authors.forename: David Sc
authors.initials: DS
authors.lastname: Lee
authors.forename: Sherwin
authors.initials: S
authors.lastname: Ting
authors.forename: Robert
authors.initials: R
authors.lastname: Liston
mesh_terms: D002543:Cerebral Hemorrhage / Q000453:epidemiology; D002908:Chronic Disease; D005260:Female; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007226:Infant Mortality; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology; D007234:Infant, Premature; D007297:Inpatients; D007363:Intensive Care Units, Neonatal; D008171:Lung Diseases / Q000453:epidemiology; D010045:Outpatients; D036801:Parturition; D011247:Pregnancy; D011256:Pregnancy Outcome