The association of macronutrients in human milk with the growth of preterm infants

Abstract

Background Breast milk is the optimal choice for feeding premature babies. However, the prevalence rate of extrauterine growth restriction in preterm infants remains high. Objectives The purpose of this study was to analyze the macronutrients present in human milk and the correlation with the growth of in-hospital preterm infants. Methods This prospective study is based on data from 99 in-hospital preterm infants younger than 37 weeks of gestational age on an exclusively human milk diet. Infants who had previously received parenteral nutrition were eligible, but they had to have reached full enteral feeding at the time that the samples were taken. A total of 3282 samples of raw human milk or donor pasteurized milk were collected. The levels of lactose, protein, fat, and energy in the samples were measured using a Miris human milk analyzer. The primary outcome was weight growth velocity (g/kg/day) which was obtained using two-point approach. Results The mean (±standard deviation) macronutrient composition per 100 mL of milk was 7.2 (±0.3) g of lactose, 1.1 (±0.2) g of true protein, 3.5 (±0.9) g of fat, and 66.9 (±6.5) kcal of energy. The protein concentration in human milk had a positive, significant correlation with body weight gain, with a coefficient of 0.41 (p < 0.001). After adjusting for gestational age, postmenstrual age, small-for-gestational age, intraventricular hemorrhage, patent ductus arteriosus or congestive heart failure, duration of total parenteral nutrition support, bottle feeding or use of orogastric tube, and ventilator support, total daily protein intake was associated with body weight growth (p < 0.001).

Macronutrient Intake from Human Milk, Infant Growth, and Body Composition at Term Equivalent Age: A Longitudinal Study of Hospitalized Very Preterm Infants

“…Importantly, higher mean daily macronutrient and energy intakes were associated with higher body weight and length at discharge despite the routine use of multicomponent human fortifiers, whereas higher fat intake was associated with higher fat mass and fat-free mass. A previous longitudinal study [32] with repeated measures of milk macronutrient content in Taiwan found that the protein content (g/dL) of human milk was positively associated with growth velocity to hospital discharge, a finding that is consistent with our results. Our study substantially extends those results by examining protein and energy intakes measured in g/kg/day, and by assessing linear growth, head growth, and body composition outcomes in addition to weight gain.…”

“…Z-scores for weight, length, and head circumference based on Fenton [ 26 ]. Z-scores for fat mass and fat-free mass based on Norris [ 32 ]. PMA is postmenstrual age.…”

Longitudinal Changes in the Concentration of Major Human Milk Proteins in the First Six Months of Lactation and Their Effects on Infant Growth

“…Third, the present study did not take maternal diet into consideration, which might have an impact on milk composition. Fourth, previous studies suggested that both the concentration of proteins in HM and daily protein intake were associated with the growth of infants [ 62 ]. However, the present study did not record the amount of HM consumed by the infants.…”

Associations of Macronutrient Intake Determined by Point-of-Care Human Milk Analysis with Brain Development among very Preterm Infants

“…These findings support the concept that eliminating existing gaps in nutrient delivery stemming from variability in human milk content may support improved brain development among very preterm infants. One emerging strategy utilizing point-of-care human milk analysis is individually targeted fortification, in which repeated measurements of milk content are used to individualize fortification for each infant, ensuring that the goal macronutrient and energy intakes are met [ 44 , 45 , 46 ]. Several small trials using this strategy for very preterm or very low birthweight (VLBW) infants have demonstrated its effectiveness in increasing macronutrient intake and improving weight gain [ 10 , 47 , 48 ].…”