A multicenter study of VLBW infants (<1501g) in Pacific Rim nurseries was undertaken to compare differences in neonatal mortality and morbidity outcomes. Prospective data was collected for all liveborn infants in 1996. Data collected included gestational age (GA), birth weight (BW), 5 minute Apgars, death, and other clinical parameters. CRIB scores were derived from these data. Odds ratios (with 95% confidence intervals) for the risk of death after controlling for known risk factors (CRIB score >5, GA ≤ 29 wks, or BW <901g) are shown below. Significant OR values (p< 0.05) are noted with *. Table

Table 1
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Neonatal death was not uniformly associated with these 3 risk factors. At most centers, an elevated CRIB score was significantly associated with mortality. None of these factors was associated with mortality in the Tokyo center. In all centers except Tokyo, the GA and BW of survivors was significantly greater than those that died (data not shown, ANOVA< p< 0.05). In Tokyo, the survivors tended to be female (p=0.07), at other centers, there was no sex difference in survivors. We conclude that there are significant differences in risk for death when controlling for known risk factors in infants at these Pacific Rim nurseries. We speculate that there may be differences in infant and maternal characteristics as well as medical and nursing care that are associated with improved outcomes despite high risk factors.

Work supported by grant from University of California.