Increased risk of bronchopulmonary dysplasia and increased mortality in very preterm infants being small for gestational age.

OBJECTIVE: The objective was to evaluate the impact of being born small for gestational age (SGA) on neonatal mortality and neonatal pulmonary morbidity in preterm infants <32 weeks of gestation.

METHODS: We reviewed the data reported prospectively to the quality assurance program of the Federal State of Hesse, Germany, from 1990 to 1996 of infants <32 weeks of gestation. SGA was defined as birth weight below the 10th percentile. Mann Whitney U tests were used to compare continuous variables and Fisher's exact tests to analyze differences in dichotomous variables between preterm SGA neonates and preterms born appropriate for gestational age (AGA). The effect of SGA and other potential risk factors for neonatal death and bronchopulmonary dysplasia, i.e., requiring a fraction of inspired oxygen >0.21 at day 28, was tested by multivariable analyses.

RESULTS: Data from 1,365 infants were analyzed. One hundred and eighty-three neonates were SGA (mean [SD] birth weight 789 [179] g; mean [SD] gestational age 28.9 [1.7] weeks) and 1,182 were AGA (mean [SD] birth weight 1,260 [348] g; mean [SD] gestational age 28.8 [2.1] weeks). Neonatal mortality and the rate of bronchopulmonary dysplasia were significantly higher in SGA neonates (23 vs. 11% and 28 vs. 14%, respectively). There was a statistically significant association of SGA with neonatal death (odds ratio [OR] = 4.54, 95% confidence interval [CI] 2.56, 8.04) and bronchopulmonary dysplasia (OR=3.80, 95% CI 2.11, 6.84).

CONCLUSION: SGA neonates below 32 weeks gestation are a high-risk group regarding neonatal mortality and neonatal pulmonary morbidity.