Neonatal Outcomes of Small for Gestational Age Preterm Infants in Canada

Abstract

To compare the effect of small for gestational age (SGA) on mortality, major morbidity and resource utilization among singleton very preterm infants (<33 weeks gestation) admitted to neonatal intensive care units (NICUs) across Canada. Infants admitted to participating NICUs from 2003 to 2008 were divided into SGA (defined as birth weight <10th percentile for gestational age and sex) and non-small gestational age (non-SGA) groups. The risk-adjusted effects of SGA on neonatal outcomes and resource utilization were examined using multivariable analyses. SGA infants (n = 1249 from a cohort of 11,909) had a higher odds of mortality (adjusted odds ratio [AOR] 2.46; 95% confidence interval [CI], 1.93–3.14), necrotizing enterocolitis (AOR 1.57; 95% CI, 1.22–2.03), bronchopulmonary dysplasia (AOR 1.78; 95% CI, 1.48–2.13), and severe retinopathy of prematurity (AOR 2.34; 95% CI, 1.71–3.19). These infants also had lower odds of survival free of major morbidity (AOR 0.50; 95% CI, 0.43–0.58) and respiratory distress syndrome (AOR 0.79; 95% CI, 0.68–0.93). In addition, SGA infants had a more prolonged stay in the NICU, and longer use of ventilation continuous positive airway pressure, and supplemental oxygen (p < 0.01 for all). SGA infants had a higher risk of mortality, major morbidities, and higher resource utilization compared with non-SGA infants.

Keywords

small for gestational age - very preterm - neonatal intensive care unit - neonatal outcomes

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