Impaired growth at birth and bronchopulmonary dysplasia classification: beyond small for gestational age.

OBJECTIVE: To correlate intrauterine and postnatal growth with bronchopulmonary dysplasia (BPD) classification at 36 weeks postmenstrual age (PMA).

STUDY DESIGN: A retrospective cohort design reviewing medical records for infants < 29 weeks gestational age (GA) born between 2008 and 2010. BPD classification using physiological definition at 36 weeks PMA and growth parameters at birth and 36 weeks PMA were compared between GA subgroups.

RESULTS: The cohort consisted of 140 infants. Median GA and birth weight (BW) were 27 weeks and 918 g, respectively. Twenty percent of infants had no BPD, 27% had mild BPD, 31% had moderate BPD, and 22% had severe BPD. While BW and GA remain major factors associated with severe BPD, we did not observe differences in weights at 36 weeks PMA. Length and head circumference were significantly impaired in infants born < 26 weeks GA at birth and 36 weeks PMA. Most importantly, all infants born < 26 weeks GA below the 25th percentile for weight developed moderate/severe BPD.

CONCLUSION: Infants born < 26 weeks GA were smaller at birth and had significant postnatal growth impairment in linear and head circumference growth. Risk of developing BPD associated with lower BW for GA appeared to occur beyond the traditional small-for-gestational age (SGA) classification.