Fig. 2.

Birth weight and gestational age-specific survival rates, bronchopulmonary dysplasia (BPD) rates, combined outcome of BPD or death rates, and mortality rates from BPD. (A) For very low birth weight infants with a birth weight less than 1,500 g. (B) For preterm infants born before 32 weeks' gestational age. The severity of BPD was defined according to the National Institute of Child Health and Human Development (NICHD) consensus definition (8). Survival, survival rate; BPD, bronchopulmonary dysplasia; PMW, postmenstrual weeks; BPD or Death, combined outcome of BPD or death rate; NICHD 1997-2002, the incidence of BPD in the National Institute of Child Health and Human Development (NICHD) Neonatal Network 1997-2002 data.