Macronutrient content of donor milk from a regional human milk bank: variation with donor mother–infant characteristics

Abstract

Better understanding of the variation in macronutrient content of human donor milk (HDM) potentiates targeted nutrition for preterm babies. The present study describes the relationship of maternal age, parity, monthly lactation stage estimate (LSEm), daily volume of milk expressed (Vd), sex, gestation and birth weight z scores with macronutrient content of HDM. Multilevel mother–infant pair ID random intercept models were performed using the predictor variables above on the outcome HDM macronutrient content determined using mid-IR spectroscopy. Mean macronutrient content was also compared by gestational age and small for gestational age (SGA) (z score < –1·28) or appropriate for gestational age (AGA) (z score ≥ –1·28) categories. A total of 2966 samples of donations from 1175 mother–infant pairs to the UK Northwest Human Milk Bank between 2011 and 2017 were analysed. Mean protein, fat, carbohydrate and calculated energy were 0·89 (SD 0·24) g/dl, 2·99 (SD 0·96) g/dl, 7·09 (SD 0·44) g/dl, and 60·37 (SD 8·41) kcal/dl (252·59 (SD 35·19) kJ/dl), respectively. Preterm SGA HDM was significantly higher in protein, fat and energy content than term AGA HDM and significantly lower in carbohydrate content than term AGA HDM after controlling for LSEm, Vd and between-subject effects. Degree of prematurity did not influence macronutrient content. Between-subject effects accounted for more of the variance in macronutrient content than the fixed effects in the model. Despite this, SGA status, as well as prematurity, may be an important determinant of macronutrient content in human milk. As bioavailability of macronutrients from HDM is uncertain, studies evaluating growth and body composition in preterm and SGA babies fed HDM are warranted.

Role of Daily Milk Volume and Period of Lactation in Nutrient Content of Human Milk: Results from a Prospective Study

“…Unlike other studies that cited gestational age at delivery as a significant predictor of milk composition [7], we found that, after controlling for all significantly associated factors, this relation was not significant. Consistent with recent studies [21,31], we found that the degree of prematurity posed no significant associations with macronutrient and sodium content.…”

“…The mean protein and fat contents were consistent with previous studies and fell within reported ranges [15,[20][21][22]. The mean sodium content was similar or slightly higher than previously reported…”

“…The mean protein and fat contents were consistent with previous studies and fell within reported ranges [15,[20][21][22]. The mean sodium content was similar or slightly higher than previously reported values, which may be due to the different populations studied, methods used, higher variability of sodium content, or different time periods [4,6].…”

It is Time for a Universal Nutrition Policy in Very Preterm Neonates during the Neonatal Period? Comment on: “Applying Methods for Postnatal Growth Assessment in the Clinical Setting: Evaluation in a Longitudinal Cohort of Very Preterm Infants” Nutrients 2019, 11, 2772

“…The administration of donor milk for twenty-eight days in neonates with BW < 1000 g and specifically without fortifier during the first two weeks of life is crucial, as the quantity of protein in donor milk is significantly lower than that in mother's own milk [7]. In a very recent paper, Li et al found that VPN with breast feeding exclusively had significantly less body weight at discharge, comparing to predominantly formula-fed neonates without any difference in adipose tissue mass.…”

Comment on Toftlund et al.

“…The supplementation that followed until about 30-32 weeks PCA was the same for babies receiving mother ' s own milk (protein 1.2-1.9 g/100 mL for the first month) and babies receiving donor milk (protein 0.9 g/100 mL). 4 Preterm formula milk offered in neonates after 32 weeks PCA contained protein 2 g/100 mL which is less than recommended by aggressive nutrition policies. 5 Attempts to breastfeed newborns after 34 weeks PCA was another cause for inadequate supplementation of mother ' s milk with protein between 34 and 40 weeks.…”