The contribution of preterm birth to the Black-White infant mortality gap, 1990 and 2000

Objectives. We evaluated whether the decline of the racial disparity in preterm birth during the last decade was commensurate with a decline in the contribution of preterm birth to the infant mortality gap. Methods. We used linked files of 1990 and 2000 data on US infant births and deaths to partition the gap between Black and White infant mortality rates into differences in the (1) distribution of gestational age and (2) gestational age-specific mortality rates. Results. Between 1990 and 2000, the Black-White infant mortality rate ratio did not change significantly (2.3 vs 2.4). Excess deaths among preterm Black infants accounted for nearly 80% of the Black-White infant mortality gap in both 1990 and 2000. The narrowing racial disparity in the preterm birth rate was counterbalanced by greater mortality reductions in White than in Black preterm infants. Extremely preterm birth (< 28 weeks) was 4 times higher in Black infants and accounted for more than half of the infant mortality gap. Conclusions. Substantial reductions in the Black-White infant mortality gap will require improved prevention of extremely preterm birth among Black infants.