(P27-091-25) Energy Density in Preterm Human Milk: A Systematic Review and Meta Analysis

Objectives: The purpose of this systematic review and meta-analysis was to describe mean energy density in human milk (HM) from mothers who delivered preterm infants.

Methods: The presented work is a part of a larger systematic review and meta-analysis to evaluate HM nutrient composition from mothers who delivered preterm. Databases (Ebsco, PubMed, and Scopus) were searched by a research librarian through July 2023. Two reviewers independently reviewed titles, abstracts, and full text articles for inclusion criteria: studies published in English and that reported HM composition from mothers who delivered preterm. Samples from countries with a Human Development Index < 0.8 and studies with a sample size of one were excluded from analysis. Random effects models were used to estimate mean estimates across studies by HM type (e.g., colostrum, transition, and mature). Colostrum HM was considered as HM collected ≤ 4d, transition between 5 - 14d, and mature as ≥ 15d. Estimates were aggregated within studies that reported multiple time points. Heterogeneity was assessed using Cochrane- I².

Results: Of the 48 studies that reported energy density, 30 that provided sufficient data were included in this meta-analysis, which represented 1,713 HM samples. 50% of the studies were conducted in the USA or Canada, 36% in the European Union, and 14% in other countries. Milk extraction methods included electric pump expression (36%), a mix of pump and hand expression (26.6%) and other manual/pump methods unspecified. Thirty-three percent evaluated energy density using bomb calorimetry, 30% using mid-infrared spectroscopy, 27% calculated energy density from macronutrient composition, and 10% did not specify. Mean energy density in preterm HM was 68.05 kcal/100mL(95% CI: 65.52, 70.59)[Q=384.71, df=29, p< 0.001; I²=89.8%]. Energy density in colostrum, transition, and mature milk was 66.64 kcal/100mL(95% CI: 63.06, 70.21), 71.93 kcal/100mL (95% CI: 67.95, 75.90), and 70.54 kcal/100mL (95% CI: 66.56, 74.51), respectively. Estimates of heterogeneity varied from 78.1% to 94.4%.

Conclusions: These data provide the most current energy density estimates for preterm HM which can better help practitioners determine appropriate preterm infant feedings.

Funding Sources: Mead Johnson