Background: Human milk is known to be the best source of nutrients for human infants. Human donor milk is an alternative when a mother’s milk is unavailable. Donor human milk is correlated with lower rates of necrotizing enterocolitis, and sepsis, and higher rates of feeding tolerance compared to formula. Donor human milk is categorized by caloric quantity, typically 20 calories/oz and 24 calories/oz. Macronutrients are considered Class II nutrients by the Food and Drug Administration and must be present at 80% or more of the value declared on the label. Donor human milk is prepared for distribution and labeled in lots as a tracking measure.
Aims: The aim of this study was to analyze multiple lots of donor human milk from one milk bank to determine if the labeled energy content met the Food and Drug Administration guidance.
Narrative: A cross-sectional analysis of frozen donor human milk was conducted. The milk was donated from a local neonatal intensive care unit at its expiration date for infant consumption. The milk was sourced from one milk bank. Five bottles were randomly selected from each lot. Two samples were taken from each bottle and were analyzed using a MIRIS human milk analyzer. The mean of the duplicate samples was recorded, and that value was used for statistical analysis. The human milk analyzer was calibrated using a Standard (MIRIS, Upsala, Sweden) after every 10th sample was analyzed. Differences within and between lots were evaluated compared to the labeled energy content for each sample for differences, with p < 0.05 considered statistically significant. Descriptive statistics of energy density and all macronutrients were calculated. Multinominal regression and analysis of variance were used to evaluate the expected energy density in relation to these macronutrient values. This data is reported elsewhere.
The mean energy labeled 20 kcal/oz was 19.6, which was not significant. The range of energy over all samples labeled 20 kcal/oz was 15.7 to 22.2 kcal/oz. There were significant differences within lots (p = 0.0265) and between lots (p = 0.0042). The low value of 15.7 kcal/oz in samples labeled 20 kcal/oz was below the Food and Drug Administration guideline.
The mean energy of 22 kcal/oz in the samples labeled 24 kcal/oz was significant (p = 0.0426). The range of energy labeled 24 kcal/oz was 18.8 to 26.2 kcal/oz. There were significant differences within lots (p = 0.0378) and between lots (p = 0.002). The low value of 18.8 kcal/oz in the samples labeled 24 kcal/oz was below the Food and Drug Administration guideline.
Conclusion: The differences found between and within the lots may challenge the consistency of calorie intake in infants receiving only donor human milk if the energy content is assumed based on the labeling. Due to the differences seen in the samples in this analysis, the energy intake may not meet the needs of ill or fragile infants fed from specific lots of donor human milk. Samples of donor human milk being fed to high-risk infants should be regularly evaluated for macronutrient content to ensure the adequacy of the feeds.
