The effect of maternal milk on neonatal morbidity of very low-birth-weight infants.

OBJECTIVE To examine the dose effect of maternal milk on neonatal morbidity of very low-birth-weight (<1.5 kg) infants. DESIGN Prospective observational study. SETTING An urban tertiary care neonatal intensive care unit and follow-up clinic. POPULATION One hundred nineteen singleton very low-birth-weight infants admitted from January 1, 1997, to February 14, 1999 (mean birth weight, 1056 g; mean gestational age, 28 weeks; 57% male; and 43% white). METHODS A comparison of the effect on neonatal outcomes of daily graded doses (1-24, 25-49, and > or = 50 mL/kg of body weight) of maternal milk through week 4 of life vs a reference group receiving no maternal milk. MAIN OUTCOME MEASURES Neonatal outcomes examined included rates of sepsis after age 5 days, retinopathy of prematurity, chronic lung disease, necrotizing enterocolitis, jaundice, duration of ventilator dependence, and length of hospital stay. RESULTS Seventy-nine infants (66%) received maternal milk, of whom 32 received at least 50 mL/kg per day through week 4 of life. Poisson regression analysis adjusting for birth weight, sex, and ethnicity revealed that the mean number of episodes of sepsis for infants receiving at least 50 mL/kg per day was lower by a factor of 0.27 (95% confidence interval, 0.08-0.95) compared with infants receiving no maternal milk. There was no effect of maternal milk on other neonatal outcomes. CONCLUSIONS A daily threshold amount of at least 50 mL/kg of maternal milk through week 4 of life is needed to decrease the rate of sepsis in very low-birth-weight infants, but maternal milk does not affect other neonatal morbidities.