Infants born at the threshold of viability in relation to neonatal mortality: Colorado, 1991 to 2003

Abstract

Objective: To determine the contribution of infants born at the threshold of viability (defined as P=0.42). The contribution of infants with birth weights PP=0.04); however, adjusted analysis showed no difference in the practice of regionalization between time periods. Regardless of time period, infants who weighed P<0.01; 95% CI 0.30, 0.52). Conclusion: Despite advances in neonatal medicine, the overall NMR in the state of Colorado remained unchanged between the time periods of 1991 to 1996 and 1997 to 2003. Infants at the threshold of viability continue to have a large impact on the Colorado NMR, making up a larger proportion of overall neonatal deaths. While the results demonstrate that the risk of mortality is significantly reduced for <750 g infants born in a level III center, the practice of regionalization has not changed between the two time periods. Improved efforts to standardize the referral practices to ensure delivery of 600 g has significantly decreased, suggesting that the boundary delineating the threshold of viability needs reevaluation, as it may have been pushed lower than previously defined.