Nitrogen and mineral balance in preterm infants fed human milks or formula.

Growth as well as nitrogen, calcium, sodium, and potassium balances were evaluated in 16 preterm infants weighing less than 1,600 g at birth, who were fed either their mother's milk, donated mature human milk, or standard commercial formula. Birthweight, gestational age, age of balance, and energy and fluid intakes were similar between groups. There were no differences between groups in the rate of growth. The infants fed their mother's milk (obtained 11-30 days into lactation) demonstrated nutrient balance similar to infants fed mature human milk. Infants fed standard commercial formula demonstrated significantly greater intake and retention of calcium compared to either human milk group. Infants fed either their mother's milk or mature human milk demonstrated net nitrogen and calcium retention below estimates of fetal nitrogen and calcium accretion. Infants fed standard formula demonstrated retentions that more closely approach the fetal estimates. This study did not demonstrate an advantage to feeding premature infants their mother's milk when compared to the feeding of mature donor milk.