The small for gestational age infant: accelerated or delayed pulmonary maturation? Increased or decreased survival?
OBJECTIVE
Small for gestational age (SGA) neonates have been considered to have accelerated pulmonary maturation and thus a lower risk for respiratory distress syndrome (RDS) than appropriate for gestational age (AGA) neonates. This, however, has not been thoroughly examined. Therefore, we compared SGA infants with AGA infants of the same gestational age (GA) with respect to risk of RDS, respiratory failure, or death.


METHODS
An indigent population born in a large county hospital.


METHODS
Multivariate analyses were performed controlling for GA alone or for GA, race, sex, and congenital anomalies. Because the proper method to identify SGA infants is unclear, we performed separate analyses using different GA estimates (obstetric or pediatric) and intrauterine growth grids (hospital-specific grids or grids for a healthy, geographically-defined population).


RESULTS
SGA infants did not fare better than AGA infants in any analysis. SGA infants had significantly increased risk in some analyses of RDS and in almost all analyses of respiratory failure or death. The risk associated with being SGA was generally comparable to that associated with male sex or White race.


CONCLUSIONS
The concept that intrauterine growth retardation accelerates lung maturation and improves outcome is not supported in comparisons of SGA and AGA infants of the same GA, sex, and race. This widely accepted concept deserves critical re-evaluation.
Tyson
J E
JE
Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas 75235-9063, USA.
Kennedy
K
K
Broyles
S
S
Rosenfeld
C R
CR
D005317:Fetal Growth Retardation / Q000503:physiopathology*; D005325:Fetal Organ Maturity; D005865:Gestational Age; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age / Q000502:physiology; D016015:Logistic Models; D008168:Lung / Q000196:embryology*; D008297:Male; D012127:Respiratory Distress Syndrome, Newborn / Q000453:epidemiology; D012131:Respiratory Insufficiency / Q000453:epidemiology; D012307:Risk Factors