Early versus late fortification of breast milk in preterm infants: a systematic review and meta-analysis

Impact of neonatal nutrition on necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the leading cause of morbidity and mortality in preterm infants. NEC is multifactorial and the result of a complex interaction of feeding, dysbiosis, and exaggerated inflammatory response. Feeding practices in the neonatal intensive care units (NICUs) can vary among institutions and have significant impact on the vulnerable gastointestinal tract of preterm infants. . These practices encompass factors such as the type of feeding and fortification, duration of feeding, and rate of advancement, among others. The purpose of this article is to review the data on some of the most common feeding practices in the NICU and their impact on the development of NEC in preterm infants. Data on the human milk bioactive component glycosaminoglycans, specifically hyaluronan, will also be discussed in the context of postnatal intestinal development and NEC prevention.

State of the evidence from clinical trials on human milk fortification for preterm infants

Infants born preterm or low birth weight are at risk for morbidity, mortality and later neuroimpairment. Appropriate early post-natal growth is associated with better outcomes in-hospital and post-discharge. Therefore, nutritional strategies that support growth may improve the long-term health of this population. Mother's milk with donor milk as a supplement are preferred sources of nutrition for these infants but may not always support growth, especially amongst infants born of very low birth weight (<1500 g) and or those with a major morbidity. Systematic reviews of randomised controlled trials to date demonstrate that multi-nutrient fortification of human milk improves in-hospital growth of preterm infants although data on long-term neurodevelopment are lacking. Further, individualised approaches to fortification based on milk analysis or the infant's metabolic response may improve growth over standard fortification. The evidence is insufficient to inform the timing of introducing fortifier, routine fortification of feeds post-discharge or routine use of fortifiers made from human instead of bovine milk. Importantly, there is insufficient data to determine if these fortification practices improve relevant clinical or neurodevelopmental outcomes. In sum, there is an urgent need for well-designed clinical trials to assess potential benefits and risks of fortification practices and at what cost.

Human Milk Fortification: A Practical Analysis of Current Evidence

Human milk (HM) with appropriate fortification is the recommended nutrition for very low birth weight (VLBW) infants. Fortification provides additional nutrients, vitamins, and minerals to support the growing preterm infant during critical periods of development. This article discusses the variability of HM including differences between maternal and pasteurized donor human milk (DHM), fortification of HM through the use of single- and multi-nutrient fortifiers, and clinical controversies including the timing of fortification, volume of feedings, and future innovations in HM fortification.

Preterm birth and human milk proteome: are we ready for individualized fortification?

PURPOSE OF REVIEW

Preterm birth is one of the most pressing clinical problems in obstetrics and neonatology worldwide. One of the most sophisticated components of human milk is the proteome and a better understanding of it can lead to precision guides for feeding preterm infants. In this review, we will examine recent research focused on the human milk proteome and individualized protein fortification of human milk.

RECENT FINDINGS

In both preterm and term birth, the protein content in mother's own milk dropped rapidly in the early postnatal period. Preterm milk had a higher protein content and contained different protein and endogenous peptide compositions compared with term milk. The peptides in gastrointestinal fluids of preterm infants still need further investigation. Individualized fortification is more superior to standard fortification, but it only focuses on the total protein amount. There is no data concerning the composition and posttranslational modifications of proteins and endogenous peptides with fortification and their longterm effects.

SUMMARY

Comprehensive identification and characterization of the human milk proteome have led to the targeted breast milk fortification theory of preterm infant feeding and has also been enriched by clinical trials. However, to achieve fortification of key proteins and/or endogenous peptides, as standard clinical practice, requires additional studies. Future research should explore the long-term effect of protein fortification and pay more attention to quality rather than quantity in relation to infant body composition and growth outcomes.

Nutrient Intake with Early Progressive Enteral Feeding and Growth of Very Low-Birth-Weight Newborns

Early nutrition is one of the most modifiable factors influencing postnatal growth. Optimal nutrient intakes for very preterm infants remain unknown, and poor postnatal growth is common in this population. The aim of this study was to assess nutrient intake during the first 4 weeks of life with early progressive enteral feeding and its impact on the in-hospital growth of very low-birth-weight (VLBW) infants. In total, 120 infants with birth weights below 1500 g and gestational ages below 35 weeks were included in the study. Nutrient intakes were assessed daily for the first 28 days. Growth was measured weekly until discharge. Median time of parenteral nutrition support was 6 days. Target enteral nutrient and energy intake were reached at day 10 of life, and remained stable until day 28, with slowly declining protein intake. Median z-scores at discharge were −0.73, −0.49, and −0.31 for weight, length, and head circumference, respectively. Extrauterine growth restriction was observed in 30.3% of the whole cohort. Protein, carbohydrates, and energy intakes correlated positively with weight gain and head circumference growth. Early progressive enteral feeding with human milk is well tolerated in VLBW infants. Target enteral nutrient intake may be reached early and improve in-hospital growth.

Early versus delayed introduction of human milk fortification in enterally fed preterm infants: A systematic review and meta-analysis

AIM

To assess effects of early versus delayed introduction of human milk fortification in preterm infants.

METHODS

We searched Cochrane Central Register of Controlled Trials, MEDLINE, Embase, PubMed and CINAHL for randomised controlled trials evaluating start time for human milk fortification in preterm infants (March 2020). Two authors assessed trial eligibility and risk of bias, extracted data and assessed evidence certainty.

RESULTS

We identified 1307 publications and included three trials (378 infants). Meta-analysis comparing fortification commencing at an enteral feed volume of ≤40 mL/kg/day versus ≥75 mL/kg/day, showed little to no difference in rates of necrotising enterocolitis (3 trials), sepsis (3 trials), feeding intolerance (2 trials) (low-quality evidence) and infant growth (1 trial, very low-quality evidence).

CONCLUSIONS

Whether early introduction of fortification, at an enteral feed volume of ≤40 mL versus delayed at ≥75 mL/kg/day improves growth or influences adverse feeding outcomes is very uncertain.