Effect of Target Fortification on Osmolality and Microbiological Safety of Human Milk Over Time

Abstract

Objectives: The fortification of human milk can result in increased osmolality, which may be associated with adverse effects for preterm infants. To evaluate the effect of target fortification on the osmolality and microbiological safety of donor human milk and raw mature milk during the first 72 hours of storage. Methods: We performed target fortification of 63 pasteurized donor human milk (PDHM) and 54 raw mature milk (RMM) samples in a laminar flow hood. Osmolality (mOsm/kg) was evaluated before fortification (T0), immediately after fortification (T1), at 6 (T2), 24 (T3), 48 (T4), and 72 hours (T5) after fortification. Microbiological analysis was performed at T0, T4, and T5. During the study, all samples were stored at 4°C. Results: Mean osmolality at each study point for PDHM and RMM were, respectively: T0: 291.4 ± 11.0 versus 288.4 ± 5.6 (P = 0.06); T1: 384.8 ± 16.7 versus 398.3 ± 23.7; T2: 393.9 ± 17.7 versus 410.1 ± 27.0; T3: 397.8 ± 17.6 versus 417.9 ± 26.1; T4: 400.0 ± 16.5 versus 420.2 ± 24.9; T5: 399.6 ± 16.5 versus 425.2 ± 25.8 (P < 0.001 from T1 to T5). Microbiological analyses were negative at each study points for PDHM. At T0 16.1% of RMM samples had positive cultures, whereas the bacterial count remained stable thought the study. Conclusions: PDHM's osmolality increases during the first 6 hours after fortification and remains stable and safe until 72 hours. RMM's osmolality increases during the first 24 hours and remains stable and safe until 72 hours. The storage at 4°C and the manipulation of PDHM and RMM samples in a laminar flow hood seem to be safe and preserve the microbiological safety of fortified pasteurized human milk until 72 hours.

Effect of fortification on the osmolality of human milk

“…Our data are reassuring since mean osmolality of DHM and preterm MOM generally remained below the AAP recommended safety cut-off value of 450 mOsm/kg [ 7 ]. These results confirm previous studies which investigated the effect of FM85 addition to DHM [ 12 , 13 ] and preterm MOM [ 14 ]. Conversely, studies which investigated the effect of fortifiers other than FM85 and Aptamil BMF on osmolality of DHM [ 6 , 15 ] and MOM [ 15 , 16 ] showed an increase of osmolality over 450 mOsm/kg.…”

“…It is noteworthy that previous studies [ 12 , 14 — 17 ], except for Piemontese et al [ 13 ], evaluated changes of osmolality only in the first 24 h after fortification. This evidence of lack of changes allowed fortification of HM once a day rather than before each feed contributing to a decrease in handling of HM and workload of nurses.…”

Protein Intakes during Weaning from Parenteral Nutrition Drive Growth Gain and Body Composition in Very Low Birth Weight Preterm Infants

“…When the infants tolerated an enteral intake ≥80 mL/kg, analysis was carried out on the macronutrient content of human milk using a mid-infrared human milk analyzer (MIRIS, Uppsala, Sweden). Then, a target human milk fortification was started using a mono-or polymeric product derived from bovine milk in order to achieve the nutrient intakes recommended by the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) guidelines [12][13][14].…”

Concentrated Preterm Formula as a Liquid Human Milk Fortifier at Initiation Stage in Extremely Low Birth Weight Preterm Infants: Short Term and 2-year Follow-up Outcomes

“…SSC30 was reported as a rescue for infants with intolerance to powder HMF [19]. The osmolarity of SSC30 remains nearly isotonic at 310 mOsm/kg, which was much lower than a pooled fortified donor milk 410.1 ± 27 mOsm/kg at 6 h [16]. Numerous fortification strategies have been proposed [11,21,38].…”

“…Fortification accuracy is imperative to prevent feeding intolerance and promote optimal health and growth [14] when feeding extremely preterm infants was preferred to be more aggressive and earlier [15]. Methods for accuracy fortification are ever proposed, including fortifying in a pooled donor milk [16] or using liquid HMF [17]. The uncertain osmolarity issue of powdered HMF in pooled human milk remains controversial.…”