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.