title: Differential Morbidity in Preterm Small versus Appropriate for Gestational Age: Perhaps Unverifiable.
abstract: OBJECTIVE
  The objective of this study was to determine the morbidity of preterm small for gestational age (SGA) infants compared with appropriate for GA (AGA).
  
  
  METHODS
  This is a secondary analysis of the randomized trial evaluating magnesium sulfate for the prevention of cerebral palsy (CP). We compared outcomes of preterm (< 37 weeks) nonanomalous infants who were SGA (birth weight < 10% for GA) versus AGA (birth weight 10-89% for GA). We compared (1) the parent trial primary outcome, a composite of stillbirth, infant death by 1 year of age, or moderate to severe CP at 2 years of age and (2) composite neonatal morbidity (CNM).
  
  
  RESULTS
  Of the 1,948 infants who met inclusion criteria, 95% were AGA and 5% were SGA. The primary outcome was similar (10 and 15%, p = 0.08), as was the CNM (24 and 25%, p = 0.89). Sample size calculations indicate that detection of a one-third higher rate of CNM among SGA compared with AGA infants requires more than 93,900 preterm births; for a one-third difference in moderate to severe CP, more than 1.4 million infants.
  
  
  CONCLUSIONS
  Owing to the prohibitive sample size required, ascertaining a difference in sequela between preterm SGA and AGA infants is possibly unverifiable.
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, UT Health Science Center at Houston, Houston, Texas.
authors.forename: Caroline C
authors.initials: CC
authors.lastname: Marrs
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, UT Health Science Center at Houston, Houston, Texas.
authors.forename: Hector
authors.initials: H
authors.lastname: Mendez-Figueroa
authors.affiliation: Department of Obstetrics-Gynecology, Eastern Virginia Medical School, Norfolk, Virginia.
authors.forename: Ibrahim A
authors.initials: IA
authors.lastname: Hammad
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, UT Health Science Center at Houston, Houston, Texas.
authors.forename: Suneet P
authors.initials: SP
authors.lastname: Chauhan
mesh_terms: D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D016022:Case-Control Studies; D002547:Cerebral Palsy / Q000453:epidemiology / Q000517:prevention & control*; D004311:Double-Blind Method; D005260:Female; D005317:Fetal Growth Retardation / Q000453:epidemiology*; D006801:Humans; D062071:Infant, Extremely Premature; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D008278:Magnesium Sulfate / Q000627:therapeutic use*; D015999:Multivariate Analysis; D018743:Perinatal Care; D011247:Pregnancy; D012044:Regression Analysis; D016896:Treatment Outcome
chemical_list: D002121:Calcium Channel Blockers; D008278:Magnesium Sulfate