It is well known that infants with established bronchopulmonary dysplasia(BPD) have poor growth. However, since the development of BPD involves the disruption of normal lung development, we hypothesize that poor growth in the early weeks of postnatal life contributes to the development of severe BPD[defined as oxygen requirement associated with characteristic X-ray changes at 36 weeks (wk) corrected gestational age (cga)]. We retrospectively evaluated 51 consecutively born neonates (1/96 to 8/96; ≤30 weeks) who had weight(wt) and head circumference (hc) measured weekly. The gestational ages(mean±sem) of infants who developed severe BPD (27.4±0.5 wk) were not different from those who did not (28.4±0.3 wk). The birth weights (979±45; 1195±56 gms), ventilation days(18.5±6.4; 3.8±1.2) and days of postnatal steroid use(2.1±0.7; 0.4±0.2) were significantly different. After controlling for these variables, wt at wk 3 of life was noted to be significantly lower (*p=0.01, repeated measures MANOVA) in babies who later developed severe BPD. Adjusted mean wts (gms) are shown.Table