The Mothers, Infants and Lactation Quality (MILQ) Study: Introduction and Study Design

The World Health Organization recommends exclusive breastfeeding for the first 6 mo of life and continued breastfeeding for 2 y or beyond. However, limited reliable, representative data on nutrient concentrations in milk from well-nourished mothers are available. Furthermore, there is a lack of data integrating human milk nutrient concentrations with the volume of milk transferred to infants during progressive stages of lactation. Accurate quantification of nutrient concentrations and milk volume is essential for setting macro- and micronutrient intake recommendations for infants and women's additional requirements for lactation. This first article in a series of 7 in this Supplement describes the Mothers, Infants, and Lactation Quality (MILQ) study conducted at sites in Bangladesh, Brazil, Denmark, and The Gambia. The MILQ study measured human milk nutrient concentrations and quantified milk volume throughout the first 8.5 mo of lactation. Validated analytical methodologies were used for nutrient quantification. The stable isotope dilution dose-to-mother method was used for milk volume measurement. A total of 1242 mother–infant dyads participated in the MILQ study. Milk volumes, milk nutrient concentrations, percentile curves, and total nutrient intakes (concentration times milk volume at each time point) are presented in the series of articles in this supplement. Comparisons are made between values in the MILQ study and those used by the Institute of Medicine (now renamed the National Academy of Medicine) to set nutrient intake recommendations for infants and lactating women, and with other selected studies. Data from the MILQ study provide a valuable resource for updating existing nutrient intake recommendations, evaluating and improving infant nutrition strategies, and assessing interventions to optimize maternal and infant nutritional status and health.