Safety of superfortification of human milk for preterm

Background: The standard preparation of fortified preterm human milk (FHM), 1 to 2 packs of human milk fortifier (HMF) in 50 milliliters of expressed breast milk (EBM), may fail to meet the theoretical requirements of ill preterm infants. The superfortified preparation of preterm human milk (SHM), 3 packs in HMF in 50 milliliters of EBM, however, leads to concerns about the osmolality of the preparation, as the higher the osmolality, the greater the risk of necrotizing enterocolitis.

Objective: We evaluated the effect of the superfortification of HMF on the osmolality of EBM

Material and method: Twelve samples of EBM were collected from mothers of a gestational age of less than 37 weeks. We measured the osmolality of the preterm human milk (PHM), FHM, and SHM. The SHM was kept at room temperature to measure the osmolality at 10 minutes after fortification.

Results: The means (SD) osmolality of the PHM and FHM were 293.9 (12.7), 335.2 (18.7) mOsm/kg H2O, respectively. The means (SD) osmolality of SHM immediately after fortification and 10 minutes after fortification at room temperature are 370.6 (17.4) and 369.8 (17.2) mOsm/kg H2O respectively.

Conclusions: The measured osmolality of SHM was less than 450 mOsm/kg H2O. This is still within the international reference range for the composition of PHM, except Ca, P, Zn, Cu, vitamin A, B1, B2, niacin, and folic acid. Therefore, SHM should be considered for feeding in only high-risk preterm neonates for short-term periods. Adverse effects need to be observed.