Mortality in Extremely Low-Birth-Weight Neonates in México City (1985–2009)

Objective. To analyze 25 years of mortality of extremely low-birth-weight (ELBW) neonates (≤1000 g) in a private hospital in Mexico City and to establish the current viability limit for ELBW neonates. Methods. We designed a prospective observational study of all ELBW neonates born between 1985 and 2009. Neonatal mortality, early neonatal mortality, and the 120-day mortality rate were analyzed in 5-year intervals by two categories of birth weight (501-750 g and 751-1000 g). Results. Among the 50,823 total births, 158 were ELBW (3.1 per 10(3)). Neonatal mortality (death ≤28 days) decreased for the 501-750 g neonates from 88.9% (1985-1989) to 55.6% (2005-1999) (P = .008) and for 751-1000 g neonates also decreased from 50% to 5.3% (P = .002). The 120-day mortality for neonates over 500 g diminished: 501-750 g neonates, 88.9% to 61.1% (P = .02) and for 751-1000 g neonates, 62.5% to 15.8% (P = .002). The highest viability limit was established in neonates who weighed ≥650 g and were ≥26 weeks in gestational age. Conclusions. The survival of ELBW neonates has improved in Mexico particularly in private hospitals, and it was more evident over the years 2004-2009. These data suggest that it is possible to increase the ELBW neonates survive in developing counties.