Donor Human Milk Fat Content Is Associated with Maternal Body Mass Index.

Introduction: Donor human milk is increasingly being utilized for both preterm and term infants when mother's milk is unavailable. With the rising prevalence of maternal overweight and obesity, it is crucial to evaluate the relationship between maternal body mass index and the fat and energy content of donor human milk. Objectives: To assess the impact of maternal body mass index on human milk fat content. Methods: A cross-sectional study was carried out using retrospective data from women who made their first human milk donation at ≥15 days postpartum at a human milk bank in São Paulo, Brazil, from January 2018 to December 2020. Data of sociodemographic, obstetric, health, and anthropometric measures were collected by the human milk bank staff. Milk fat and energy content were determined using the crematocrit test. Analysis of variance and multiple linear regression were used to compare means of crematocrit and fat. We determined the p-values using a test of heterogeneity and linear trend and presented the one with the lower p-value. Results: Most donors were between 25 and 35 years old, had higher education, were employed, and lived with a partner. At the time of milk donation, 40.9% of women were overweight or obese. The fat (1.09 g/dL) and energy (9.83 kcal/dL) content of human milk were higher in obese donor compared with eutrophic donors. Conclusions: The fat and energy content of human milk were associated with maternal body mass index, suggesting the potential value for selective use of high fat and high calorie donor milk for very low birthweight or premature infants.