Objective: To determine the changes in availability of neonatal intensive care for extremely low birthweight (ELBW) infants, and the consequences of a lack of availability.
Design and setting: Population-based cohort study of consecutive ELBW infants born in the state of Victoria during four distinct eras.
Participants: All livebirths weighing 500-999 g in Victoria in the calendar years 1979-1980 (n = 351), 1985-1987 (n = 560), 1991-1992 (n = 429), and 1997 (n = 233).
Main outcome measures: Changes over time in the proportions of ELBW infants offered intensive care, the proportions that were "outborn" (born outside level 3 perinatal centres), and their survival rates and quality of survival compared with "inborn" infants.
Results: The proportions of ELBW infants offered intensive care increased over time and were significantly higher in heavier infants. The proportion of outborn ELBW infants was 30% in 1979-1980, falling to 9% by 1997. The difference in survival rates between inborn and outborn infants widened progressively over time: the survival advantages for inborn infants over outborn infants were 12.0% in 1979-1980, 30.1% in 1985-1987, 36.5% in 1991-1992, and 43.6% in 1997. For survivors, the quality of life was significantly better for inborn infants in two of the four eras.
Conclusions: Neonatal intensive care has been increasingly available for ELBW infants in Victoria over the period 1979 to 1997. The gap in survival rates between outborn and inborn infants has widened, and the quality of life of outborn survivors is inferior.