title: Neurodevelopmental outcomes of triplets or higher-order extremely low birth weight infants.
abstract: BACKGROUND
  Extremely low birth weight twins have a higher rate of death or neurodevelopmental impairment than singletons. Higher-order extremely low birth weight multiple births may have an even higher rate of death or neurodevelopmental impairment.
  
  
  METHODS
  Extremely low birth weight (birth weight 401-1000 g) multiple births born in participating centers of the Neonatal Research Network between 1996 and 2005 were assessed for death or neurodevelopmental impairment at 18 to 22 months' corrected age. Neurodevelopmental impairment was defined by the presence of 1 or more of the following: moderate to severe cerebral palsy; mental developmental index score or psychomotor developmental index score less than 70; severe bilateral deafness; or blindness. Infants who died within 12 hours of birth were excluded. Maternal and infant demographic and clinical variables were compared among singleton, twin, and triplet or higher-order infants. Logistic regression analysis was performed to establish the association between singletons, twins, and triplet or higher-order multiples and death or neurodevelopmental impairment, controlling for confounding variables that may affect death or neurodevelopmental impairment.
  
  
  RESULTS
  Our cohort consisted of 8296 singleton, 2164 twin, and 521 triplet or higher-order infants. The risk of death or neurodevelopmental impairment was increased in triplets or higher-order multiples when compared with singletons (adjusted odds ratio: 1.7 [95% confidence interval: 1.29-2.24]), and there was a trend toward an increased risk when compared with twins (adjusted odds ratio: 1.27 [95% confidence: 0.95-1.71]).
  
  
  CONCLUSIONS
  Triplet or higher-order births are associated with an increased risk of death or neurodevelopmental impairment at 18 to 22 months' corrected age when compared with extremely low birth weight singleton infants, and there was a trend toward an increased risk when compared with twins.
authors.affiliation: West Coast Neonatology, All Children's Hospital, 601 Fifth Street South, OCC 5th Floor, St Petersburg, FL 33701, USA. rajan.wadhawan@allkids.org
authors.forename: Rajan
authors.initials: R
authors.lastname: Wadhawan
authors.forename: William
authors.initials: W
authors.lastname: Oh
authors.forename: Betty R
authors.initials: BR
authors.lastname: Vohr
authors.forename: Lisa
authors.initials: L
authors.lastname: Wrage
authors.forename: Abhik
authors.initials: A
authors.lastname: Das
authors.forename: Edward F
authors.initials: EF
authors.lastname: Bell
authors.forename: Abbot R
authors.initials: AR
authors.lastname: Laptook
authors.forename: Seetha
authors.initials: S
authors.lastname: Shankaran
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Stoll
authors.forename: Michele C
authors.initials: MC
authors.lastname: Walsh
authors.forename: Rosemary D
authors.initials: RD
authors.lastname: Higgins
mesh_terms: D000328:Adult; D002657:Child Development / Q000502:physiology*; D002658:Developmental Disabilities / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D052577:Infant, Extremely Low Birth Weight / Q000254:growth & development*; D007231:Infant, Newborn; D008297:Male; D016017:Odds Ratio; D011247:Pregnancy; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D014310:Triplets; D014481:United States / Q000453:epidemiology