Longitudinal Changes of Mineral Concentrations in Preterm and Term Human Milk from Lactating Swiss Women

Preterm babies represent a vulnerable population that requires a high level of care, including nutritional support, to offset the risk of nutritional deficiencies and associated adverse health outcomes. Breastfeeding is the gold standard source of nutrition for term infants and is also highly recommended for preterm infants. However, because of the risk of inadequate nutrient intakes, the fortification of mothers’ own milk or donor human milk (HM) is generally recommended for very preterm infants to enhance the protein, energy, and micronutrients intake.

Iron, zinc, copper, iodine, selenium, calcium, phosphorus, and magnesium, but also potassium and sodium are essential minerals or trace elements. Term infants are generally born with adequate stores of minerals, the accrual of which occurs during the third trimester of pregnancy. A consequence of being born before term is a high risk of mineral shortfalls. Minerals are essential and need to be provided at a level to meet the in utero accretion rates to favor catch-up.

This study precisely describes the concentration of zinc, copper, iodine, selenium, iron, calcium, phosphorus, magnesium, potassium, and sodium in HM from mothers of preterm (28–32 weeks of gestation) infants over a period of 16 weeks and compares preterm HM mineral content with that of milk from mothers of full term (>37 weeks of gestation) infants at equivalent infant postpartum and postmenstrual ages. An accurate understanding of HM mineral content and its potential sources of variability will facilitate HM mineral fortification for preterm babies.