Nutrient composition of preterm mother's milk and factors that influence nutrient content

Protein and Free Amino Acid Composition of Preterm Human Milk: A Systematic Review and Meta-analysis

The composition of total protein and free amino acids (FAA) in preterm human milk (HM) is crucial for optimizing infant growth and development. The objective of this systematic review and meta-analysis is to quantify the amount of true, crude, and unspecified protein and FAA in preterm HM. EBSCO, PubMed, and Scopus databases were searched up to July 2023 measuring total protein and FAA in preterm HM. Two reviewers, working independently, screened all titles and abstracts using Covidence software to identify studies meeting inclusion criteria [preterm <37 wk; Human Development Index >0.8; cross-sectional, case-controlled (n > 1), prospective cohort, and randomized clinical trials; English language]. Random-effects models were used to estimate mean protein and FAA content across studies. Data were aggregated for studies reporting multiple estimates (e.g. across time). Heterogeneity was estimated using I2 and publication bias using Kendall tau rank correlation coefficient. Of the 884 articles identified, a total of 66 original studies were included for the meta-analysis comprising an estimated 30,421 preterm HM samples. Preterm colostrum (<4 d) contained the highest mean (95% confidence interval) true protein at 2. 32 (1. 96, 2. 68) g/100 mL, followed by transition preterm HM (5-14 d) mean true protein of 1. 77 (1. 60, 1.93) g/100 mL. Mature (>14 d) preterm HM had the lowest mean true protein content at 1.46 (1.34, 1.59) g/100 mL. Glutamate was the most prevalent FAA reported. This systematic review provides updated estimates of protein and FAA concentrations in preterm HM. There was significant variability in the quality of studies, completeness of the reported results, and analytical methodologies across studies. This trial was registered at PROSPERO as CRD42023445191.

Improved linear growth after routine zinc supplementation in preterm very low birth weight infants

BACKGROUND

This study was designed (1) to compare growth, morbidity and mortality in < 33-week gestational age (GA) (very preterm, VPT) or very low birth weight (BW < 1500 grams, VLBW) infants before (Epoch-1) and after implementing routine enteral zinc (Zn) supplementation (Epoch-2) to meet recommendations, and (2) to assess serum Zn levels and associated variables.

METHODS

Single-center prospective cohort of 826 infants. The primary outcome was the change (Δ) in Z-scores of accurate length (Δlengthz), weight and head circumference from birth to discharge home.

RESULTS

In Epoch-2 vs Epoch-1 Δlengthz adjusted for confounding variables increased by 0.27 [95% confidence interval (CI) 0.13, 0.42, P < 0.001]. However, morbidity and mortality did not change. In Epoch-2 Zn decreased with GA and postnatal age: low ( < 0.74 mcg/mL) levels were observed in 51% infants. Retinopathy of prematurity (ROP) was independently associated with the lowest Zn [adjusted odds ratio 0.042 (CI 0.006, 0.306), area under the curve=0.928].

CONCLUSION

Routine enteral Zn supplementation was independently associated with improved linear growth but did not prevent occurrence of low Zn. ROP was independently associated with the lowest Zn.

IMPLICATIONS

Multicenter studies are needed to assess whether dosage of enteral Zn should be increased and whether Zn could help prevent ROP.

IMPACT

Implementation of routine enteral zinc (Zn) supplementation was associated with improved linear growth from birth to discharge and a more frequent physiologic growth curve in preterm very low birth weight infants. Serum Zn levels decreased with gestational age and with postnatal age. Low serum Zn levels were observed frequently despite routine Zn supplementation as currently recommended, which suggests a need to re-evaluate current enteral zinc supplementation guidelines for this population. Retinopathy of prematurity among infants < 33 weeks' gestation was independently associated with low gestational age, low birthweight, stage of bronchopulmonary dysplasia and the lowest serum Zn level.

Improved Growth Velocity Using a New Liquid Human Milk Fortifier in Very Low Birth Weight Infants: A Multicenter, Retrospective Study

This study aimed to compare growth outcomes and tolerance among very low birth weight (VLBW) infants receiving a new, liquid human milk fortifier (LHMF-NEW) or a human milk fortifier-acidified liquid (HMF-AL).Retrospective, multicenter study of 515 VLBW infants in three regional neonatal intensive care units. The primary objective was to compare growth velocity (g/kg/d) during fortification between groups by repeated measures regression. Secondary outcomes of interest were feeding tolerance and the incidence of late-onset sepsis, necrotizing enterocolitis, and metabolic acidosis. Student's t, analysis of variance, Wilcoxon, and Kruskal-Wallis tests were used for numeric variables, or chi-squared and Fisher's exact test for categorical variables.No demographic differences were identified between the groups (HMF-AL, n = 242; LHMF-NEW, n = 273). Growth velocity during fortification was significantly higher in the group receiving LHMF-NEW, despite relatively similar total fluid, calorie, or protein intake (p = 0.001). Feeding intolerance was comparable between fortifiers. Necrotizing enterocolitis and late-onset sepsis did not differ between groups and metabolic acidosis was diagnosed less frequently with the LHMF-NEW. Anthropometric measures at discharge and length of stay were comparable.Infants receiving human milk fortified with the LHMF-NEW had faster growth velocity during fortification, similar tolerance, and less metabolic acidosis compared with an earlier cohort of infants who received human milk fortified with an HMF-AL. · Among VLBW infants, using an LHMF-NEW resulted in a faster growth velocity in weight during several weeks of fortification than using the previous HMF-AL.. · The incidence of feeding intolerance (stopping feeds >8 hour) in any given week of fortification was low and not different between groups. Also, late-onset sepsis and necrotizing enterocolitis were uncommon with no differences between groups, whereas the incidence of metabolic acidosis was lower in infants receiving the LHMF-NEW.. · No differences in length of stay or anthropometrics at discharge were identified..

Benefits of an Exclusive Human Milk Diet in a Very Preterm Infant With an Ileostomy: A Case Report

Mother's milk (MOM) provides numerous benefits for very preterm infants; however, it requires fortification to achieve appropriate nutrition intake. Although cow milk-based human milk fortifier (CMHMF) is widely used in Japan, it poses a risk of fatty acid calcium formation in infants with ileostomy. An exclusive human milk diet (EHMD) uses only human milk products to fortify MOM or donor human milk using a human milk-based human milk fortifier. Compared to CMHMF, EHMD reduces feeding intolerance and necrotizing enterocolitis in premature infants and may be safely used in infants with an ileostomy. However, specific studies addressing the nutritional effects of EHMD in these patients are lacking. This case report discusses the potential benefits of an EHMD in an infant undergoing ileostomy. The male infant, weighing 742 g, was delivered by emergency cesarean section at the postmenstrual age of 26 weeks and three days. On day eight of life, the patient underwent intestinal resection and anastomosis for a localized intestinal perforation. CMHMF could not be used because of the risk of fatty acid calcium stone formation. Given concerns regarding malnutrition, the case was administered an EHMD. Following the introduction of EHMD, his weight gain improved from 5 g/day to 17 g/day, and his z-score improved from -0.8 standard deviation (SD) to +0.3 SD. No adverse events were observed. It is suspected that the improvement in the anthropometric data was attributable to the establishment and maintenance of full feeding volumes alongside the EHMD, which ensured adequate nutrition and increased nutritional intake. This case suggests that EHMD may be a safe and effective nutritional strategy to promote optimal growth and development in infants undergoing abdominal surgery.

Nitrogen sources in donor human milk: True protein, nonprotein nitrogen, and amino acid profile

BACKGROUND

Devices measuring the macronutrient content of human milk are commonly used to assist with clinical decision-making. It is unknown if these devices accurately measure protein content in donor human milk (DHM). Our objective is to quantify the nitrogen sources and protein content in commercial DHM.

METHODS

The total nitrogen content (Dumas method) and nonprotein nitrogen content (Kjeldahl method) was measured in triplicate from six commercial DHM samples with protein content noted on the labels. In addition, the amino acid content was measured in 15 commercial DHM samples and protein content in each sample was calculated. The calculated protein content for each DHM sample was compared for consistency.

RESULTS

The nonprotein nitrogen content in DHM was consistently higher (0.33 ± 0.05 g/g) than previous reports, leading to overreporting of protein content on DHM labels by a median value of 0.15 g/dl (range 0.02-0.23 g/dl). Similarly, calculation of the protein content from the total nitrogen content with an assumption of 20% (grams per gram) nonprotein nitrogen consistently overrepresented the protein content as determined from the amino acid profile for DHM.

CONCLUSION

Common methods for assessing the macronutrient content of human milk may overestimate the protein content of DHM.

Immediate fortification of human milk with a bovine milk-derived human milk fortifier in very low birth weight infants: a randomized clinical trial

OBJECTIVE

Double-blind randomized control trial of early addition of a bovine milk-derived human milk fortifier (HMF) in very low birth weight (VLBW) infants (NCT05228535).

METHODS

VLBW infants were randomized to receive bovine milk-derived HMF with first feedings or delayed fortification at 80 ml/kg/day. Anthropometrics were assessed weekly through 36 weeks postmenstrual age (PMA). Unadjusted and adjusted (race, gender, gestational age, and birth weight) differences between study arms were examined using two-sample t-test and ANCOVA, respectively.

RESULTS

Fifty-two VLBW infants (57% female, 60% Black) were enrolled. Baseline demographics did not differ between groups. Weight velocity at DOL 28 did not differ between study arms. Secondary outcomes including NPO occurrence, incidence of metabolic acidosis, NEC, retinopathy, or late-onset sepsis did not differ between groups.

CONCLUSION

Immediate fortification of enteral feedings with a bovine milk-derived HMF appears safe and well-tolerated although no clear growth benefit could be established.

Urine sodium concentration and 28-day weight velocity in preterm infants: A retrospective cohort study

BACKGROUND

Urine sodium concentration has been suggested as a marker to guide enteral sodium supplementation in preterm infants; however, no previous data have demonstrated relationships between urine sodium concentration and postnatal growth.

METHODS

We performed a single-center retrospective cohort study on 224 preterm infants admitted to the neonatal intensive care unit at the Children's Hospital of Georgia between January 2010 and July 2022. Spot urine sodium was measured in preterm infants (<34 weeks postmenstrual age [PMA]) between days of life (DOLs) 7 and 28. Our exposure of interest was spot urine sodium concentration (milliequivalents per liter) obtained between postnatal days 7 and 28, and our primary outcome was weight velocity (grams per kilograms per day) determined at DOL 28. Statistical relationships were assessed by multivariate analysis with subgroup comparisons by Student t test and analysis of variance.

RESULTS

In 224 preterm infants (199 ± 17 days, 56% male, 71% Black), urine sodium concentration did not associate with weight velocity at DOL 28 and 36 weeks PMA. Urine sodium concentration was weakly associated with gestational age at birth, and Black preterm infants had higher urine sodium values when compared with "other," but not White preterm infants.

CONCLUSION

Spot urine sodium during the first month of life does not associate with weight velocity at DOL 28 or 36 weeks PMA.

A Review: The Effect of Bovine Colostrum on Immunity in People of All Ages

Bovine colostrum provides newborn calves with strong passive immunity, which will further affect the immunity of their offspring. Compared with other commercial dairy products, bovine colostrum emphasizes the limit of aflatoxin M1, pathogenic bacteria, microorganisms, antibiotics, stimulants, and other items, so it is safe to use. There are many reports that the use of bovine colostrum as a breast milk fortifier for preterm infants provides necessary immune support for premature infants, but the selection of bovine colostrum products chosen must be free of Bacillus cereus because they are very dangerous for premature infants. This also emphasizes that for the bovine colostrum that is used in preterm infants, more clinical research support is needed. At the same time, it should also be emphasized that the composition of BC is different from that of human colostrum, in particular, the main protein of BC is casein, while the main protein in breast milk is whey protein, especially α-lactalbumin, which together with ovalbumin is still the reference protein with the best biological value, especially for muscles. Therefore, bovine colostrum is currently not a complete substitute for breast milk. In recent years, in addition to reports of bovine colostrum use in preterm infants, studies have also found that bovine colostrum has immunomodulatory and promoting effects in adolescents, adults, and the elderly. This suggests that bovine colostrum has the potential to provide appropriate immune support for people of all ages. Therefore, this study aimed to evaluate the quality of nutritional characteristics of bovine colostrum on three dimensions. The effects of bovine colostrum on people of all ages is a narrative review of the effects of bovine colostrum on immunity in people of all ages. This review identified several classes of immunoactive substances in bovine colostrum, including immunoglobulins, cytokines, and enzymes, and compared the nutritional composition of bovine colostrum with mature milk, colostrum and mature milk in full-term breast milk, and colostrum and mature milk in preterm breast milk, to demonstrate that bovine colostrum provides a rich range of immunoactive components. In addition, the influencing factors affecting the quality of bovine colostrum (immunoglobulin) were reviewed, and it was found that individual differences, environmental factors, and processing methods had a great impact on the quality of BC. More importantly, the immunomodulatory effects of bovine colostrum in people of all ages were reviewed in detail (with an emphasis on preterm infants and immunocompromised children in neonates) as evidence to support the immunity effects of colostrum in people of all ages. This review hopes to use the above evidence to make people understand the health role of bovine colostrum as having a human immunomodulatory effect, and at the same time, when seeing the potential value of bovine colostrum in the future, the limitations of its application should also be deeply re-explored, such as lactose intolerance, allergies, etc., to provide effective solutions for the wide application of bovine colostrum.

Mineral supplementation for very preterm infants fed fortified human milk

OBJECTIVES

The safety and feasibility of human milk fortification with bovine colostrum (BC) were investigated in very preterm infants (FortiColos trial, NCT03537365). The BC product contained lower calcium, phosphate, and iron levels compared to the conventional fortifier (CF). We tested whether fortification with BC plus extra phosphate was sufficient to support the infants' mineral status assessed by blood biochemistry.

METHODS

In a randomised controlled trial (FortiColos, NCT03537365), mineral status was compared after fortification with BC versus CF. Blood calcium, phosphate, and haemoglobin were determined before and up to 3 weeks after the start of fortification (at the mean age of 8-9 days). The maximum supplemental doses of calcium, phosphate, and iron given were retrieved from patient medical records. Results were adjusted for gestational age, birth weight, and enteral nutrition with the mother's own milk and/or donor human milk.

RESULTS

Blood values of calcium, phosphate, and haemoglobin were similar between groups. Infants in both groups required supplementation with calcium and phosphate, but infants fed BC required higher maximum doses of phosphate and calcium (p < 0.05) to maintain acceptable blood values. Regardless of fortification groups, the most immature (<29 weeks of gestation) and small for gestational age infants showed a higher risk for requiring additional phosphate (odds ratio [OR]: 3.9, p < 0.001; OR: 2.14, p = 0.07, respectively).

CONCLUSIONS

The use of BC as a fortifier for human milk requires additional phosphate and calcium relative to a CF. Regardless of the fortification product, the most immature and small infants require additional mineral supplementation.

Health disparities in preterm births

Introduction

Black African American (B/AA) women have a 2-fold to 3-fold elevated risk compared with non-Hispanic White (W) women for preterm birth. Further, preterm birth is the leading cause of mortality among B/AA infants, and among survivors, preterm infant adverse health outcomes occur disproportionately in B/AA infants. Racial inequities in maternal and infant health continue to pose a public health crisis despite the discovery >100 years ago. The purpose of this study was to expand on reported preterm infant outcome disparities. A life-course approach, accumulation of lifelong stress, including discrimination, may explain social factors causing preterm birth rate and outcome inequities in B/AA mothers.

Methods

Anthropometric measures and clinical treatment information for 197 consented participants were milled from electronic health records across 4 years. The Neonatal Infant Stressor Scale was used to tally acute and chronic painful/stressful procedures. Neurobehavioral differences were investigated using the Neonatal Intensive Care Unit (NICU) Network Neurobehavioral Scale.

Results

B/AA mothers gave birth to preterm infants earlier than W mothers. NICU hospitalization stays were extended more than 2 weeks for the significantly smaller B/AA preterm infants in comparison to the age-matched W preterm infants. A higher number of chronic lifesaving procedures with demonstrated altered stress response patterns were recorded for B/AA preterm infants.

Discussion

This cross-sectional analysis of preterm birth rates and preterm infant developmental and neurodevelopmental outcomes are presented in the context of NICU stress and pain, with attendant implications for infant mortality and future health disparities. Preterm birth rate and outcome inequities further support the need to develop interventions and policies that will reduce the impact of discrimination and improve social determinants of health for Black, Indigenous, and other People of Color.

Quantification and reporting of vitamin D concentrations measured in human milk by LC-MS/MS

Vitamin D is essential for optimal bone health, and vitamin D deficiency has been associated with an increased risk of adverse pregnancy, growth and developmental outcomes. In early life, and in the absence of endogenous vitamin D production from UVB light, infants are reliant on vitamin D stores established in utero and the vitamin D supply from human milk (HM). However, comprehensive data on vitamin D in HM is lacking. Thus, in this review we explore the application of liquid-chromatography tandem mass spectrometry (LC-MS/MS) to the assessment of vitamin D in HM. We discuss the challenges of extracting and measuring multiple vitamin D metabolites from HM including the frequent requirement for a large sample volume, and inappropriate poor sensitivity. Shortcomings in the reporting of experimental procedures and data analysis further hinder advances in the field. Data collated from all studies that have applied LC-MS/MS reveal that, in general, cholecalciferol concentration is greater and more variable than 25-hydroxyvitamin D concentration, and that the vitamin D content of HM is low and less than the currently recommended dietary requirement of infants, although maternal supplementation can increase the vitamin D content of HM. Improvements in analytical methods and their validation and larger, more representative studies are required to better characterize HM milk vitamin D metabolite concentrations and their relationship with maternal status. These data are essential to understand relationships with infant health and to inform public health policies around vitamin D fortification and supplementation.

Early-life sodium deprivation programs long-term changes in ingestive behaviors and energy expenditure in C57BL/6J mice

Postnatal growth failure remains a significant problem for infants born prematurely, despite aggressive efforts to improve perinatal nutrition. Though often dysregulated in early life when children are born preterm, sodium (Na) homeostasis is vital to achieve optimal growth. We hypothesize that insufficient Na supply in this critical period contributes to growth restriction and programmed risks for cardiometabolic disease in later adulthood. Thus, we sought to ascertain the effects of prolonged versus early-life Na depletion on weight gain, body composition, food and water intake behaviors, and energy expenditure in C57BL/6J mice. In one study, mice were provided a low (0.04%)- or normal/high (0.30%)-Na diet between 3 and 18 wk of age. Na-restricted mice demonstrated delayed growth and elevated basal metabolic rate. In a second study, mice were provided 0.04% or 0.30% Na diet between 3 and 6 wk of age and then returned to standard (0.15%)-Na diet through the end of the study. Na-restricted mice exhibited growth delays that quickly caught up on return to standard diet. Between 6 and 18 wk of age, previously restricted mice exhibited sustained, programmed changes in feeding behaviors, reductions in total food intake, and increases in water intake and aerobic energy expenditure while maintaining normal body composition. Although having no effect in control mice, administration of the ganglionic blocker hexamethonium abolished the programmed increase in basal metabolic rate in previously restricted mice. Together these data indicate that early-life Na restriction can cause programmed changes in ingestive behaviors, autonomic function, and energy expenditure that persist well into adulthood.

High protein content in breast milk from South African mothers of preterm infants

AIM

Macronutrient and energy content of human milk are largely assumed for fortification practices. The aim was to explore macronutrient and energy content of transition and mature human milk from South African mothers of preterm infants with a birth weight <1800 g. Secondary objectives compared day to night milk; and explored associations with selected innate factors.

METHODS

In this single-centre, observational study macronutrient and energy content of day, night and mixed samples of transition (first 14 days of life) and mature (from Day 15 of life) human milk were analysed with mid-infrared spectroscopy.

RESULTS

In total, 116 samples (38 days; 37 night; 41 mixed) from 47 mothers were retained for statistical analysis. Mean true protein, carbohydrate, fat and energy content of mixed samples per 100 mL were 1.5 ± 0.4 g, 7.2 ± 0.7 g, 3.5 ± 0.9 g and 69.4 ± 9.9 kcal, respectively. Mixed transition milk (n = 9) had 1.9 ± 0.3 g protein and 67.4 ± 9.6 kcal and mixed mature milk (n = 32) 1.4 ± 0.4 g protein and 70.0 ± 10.1 kcal, per 100 mL.The protein content of transition (p = 0.004) and mature (p = 0.004) milk were significantly higher than published data. Transition milk: 1.5 g protein, 65 kcal; mature milk: 1.2 g protein, 72 kcal per 100 mL. Night samples had less fat (p = 0.014) and energy (p = 0.033) than day samples. With increasing day of life protein content declined (p = 0.003).

CONCLUSION

The protein content of human milk from South African mothers of preterm babies differs from published data and has implications for human milk fortification practises.

Nutrient Composition of Donor Human Milk and Comparisons to Preterm Human Milk

BACKGROUND

Human milk is the preferred diet for very low birth weight (VLBW, <1500 g) infants. When mother's own milk is unable to meet the needs of VLBW infants, donor human milk (DHM) is the preferred alternative. Unfortunately, the composition of DHM remains elusive and no comparative studies between preterm human milk and DHM have been performed previously.

OBJECTIVES

We aimed to analyze the nutrient content of commercial pooled DHM and compare nutrient content in DHM with that of early and mature preterm human milk.

METHODS

We analyzed nutrient content in 15 DHM samples provided from 7 commercial milk banks including calories, carbohydrate, fat, protein, sodium, chloride, potassium, zinc, calcium, phosphorus, magnesium, and vitamin D and compared each nutrient to early (7 d of life) and mature (28 d of life) preterm human milk samples (n = 28-36 per nutrient, gestational age = 28 ± 3 wk). Protein-to-energy ratio and carbohydrate-to-nonprotein energy ratio were calculated for each sample and compared.

RESULTS

Mean values for all macro- and micronutrients in DHM are reported. In comparison to early or mature preterm human milk, DHM had significantly lower protein, sodium, chloride, potassium, and zinc content. Calorie, carbohydrate, calcium, phosphorus, magnesium, and vitamin D content did not differ statistically between DHM and early or mature preterm human milk. Fat content was modestly lower in early but not mature human milk when compared with DHM.

CONCLUSIONS

We provide mean values for several macro- and micronutrients for DHM and identify key differences between DHM and preterm human milk, which may be considered when designing human milk-based feeding plans. This study was registered at clinicaltrials.gov as NCT05742815.

Early Human Milk Fortification in Infants Born Extremely Preterm: A Randomized Trial

OBJECTIVES

Enteral nutrition with unfortified human milk during the first 2 postnatal weeks often leads to cumulative protein and energy deficits among preterm infants. Fortified human milk administered soon after birth could increase fat-free mass (FFM) and improve growth in these infants.

METHODS

This was a masked, randomized trial. Starting on feeding day 2, extremely preterm infants 28 weeks or younger fed maternal or donor milk were randomized to receive either a diet fortified with a human-based product (intervention group) or a standard, unfortified diet (control group). This practice continued until the feeding day when a standard bovine-based fortifier was ordered. Caregivers were masked. The primary outcome was FFM-for-age z score at 36 weeks of postmenstrual age (PMA).

RESULTS

A total of 150 infants were randomized between 2020 and 2022. The mean birth weight was 795±250 g, and the median gestational age was 26 weeks. Eleven infants died during the observation period. The primary outcome was assessed in 105 infants (70%). FFM-for-age z scores did not differ between groups. Length gain velocities from birth to 36 weeks PMA were higher in the intervention group. Declines in head circumference-for-age z score from birth to 36 weeks' PMA were less pronounced in the intervention group.

CONCLUSIONS

In infants born extremely preterm, human milk diets fortified soon after birth do not increase FFM accretion at 36 weeks' PMA, but they may increase length gain velocity and reduce declines in head circumference-for-age z scores from birth to 36 weeks' PMA.

Trend and Predictors of Breastmilk Feeding among Very-Low-Birth-Weight Infants in NICU and at Discharge

Mothers' own milk (MOM) for premature babies is considered a life-saving drug for its proven protective action against the complications of prematurity and for effects on outcome in the short and long term, especially neurological ones. We studied the use of MOM for infants weighing <1500 g for a period of 5 years, evaluating the trend over time and the impact of some variables on human milk feeding performance. Statistical comparisons concerned the rate of feeding with breast milk during a stay in an NICU and at discharge with respect to two types of variables: (1) maternal and neonatal characteristics (gestational age, birth weight, type of pregnancy (whether single or twin), maternal age) and (2) feeding characteristics (time of the start of minimal enteral feeding and availability of MOM, days until the achievement of full enteral feeding). Group comparisons were performed using ANOVA or t-test for continuous variables and Pearson chi-squared test or Fisher exact test for categorical variables. We observed an increase, between 2017 and 2021, in MOM use (p = 0.003). The availability of the own mothers' milk occurred, on average, on the fourth day of life and improved over the years. The start of minimal enteral feeding (MEF) with human milk averaged 1.78 days, and 54.3% of VLBWs received MEF with donor milk on the first day of life. The average percentage of feeding with the mothers' milk at discharge was 47.6%, with 36.1% of exclusive MOM and an increase from 45.8% in 2017 (33.3% exclusive) to 58.82% (41.18% exclusive) in 2021. The mean average daily growth of the weight improved (p < 0.001) during this period, and there was no statistical difference between infants fed with maternal milk and those fed with bank milk. Older maternal age, early-start feeding with maternal milk and low gestational age had a statistically significant impact on feeding with MOM at discharge.

Sodium and Growth in Preterm Infants: A Review

Aim

This article is intended to review the relationship between sodium homeostasis and growth, outline reasons why preterm infants may become sodium deficient, and share data from our group and others regarding the potential benefits of dietary sodium supplementation.

Background

Despite tremendous efforts over the past 20 years to optimize neonatal nutrition, postnatal growth failure in preterm infants remains a significant problem. Compelling associations have been identified between in-hospital growth failure and cardiometabolic and neurodevelopmental disorders, heightening the need to further identify the optimal nutritional needs of preterm infants.

Results

The impact of sodium deficiency may have on somatic growth is poorly studied and reported upon within the human literature. In contrast, animal studies dating back almost 100 years highlight the nutritional importance of dietary sodium. Sodium homeostasis during early postnatal life is understudied and underappreciated by neonatologists.

Conclusion

Insufficient sodium intake during early life is likely a critical yet underappreciated contributor to growth failure. Total body sodium depletion may be an important risk factor driving complications of premature birth.

Clinical significance

Increased awareness of sodium homeostasis in preterm infants may improve outcomes in this population. Sodium intake recommendations are provided based on the interpretation of currently available literature.

Growth after implementing a donor breast milk program in neonates <33 weeks gestational age or birthweight <1500 grams: Retrospective cohort study

BACKGROUND

Donor breast milk (DBM) feeding has been associated with less growth than formula in preterm infants. Zinc content in DBM is insufficient to support growth in preterm infants.

OBJECTIVE

To compare growth from birth to discharge, macro- and micronutrient intake and the frequency of poor growth before (Epoch-1) and after (Epoch-2) implementing a DBM program.

METHODS

Retrospective cohort study of 1069 infants born at < 33 weeks' gestational age or birthweight < 1500 g and fed using our adjustable feeding protocol with accurate serial length measurements. Growth was assessed by changes in Z-scores of weight, length and fronto-occipital circumference from birth to discharge.

RESULTS

Growth did not decrease significantly in Epoch-2. However, energy and protein intake increased by 5% and frequency of zinc and vitamin D supplementation increased by >30%.

CONCLUSIONS

DBM implementation did not significantly decrease growth from birth to discharge using our adjustable feeding protocol.

Fortified Donor Human Milk Frequently Does Not Meet Sodium Recommendations for the Preterm Infant

We measured the sodium content of donor human milk (DHM) and calculated the estimated intake at a feeding volume of 160 mL/kg/day. The mean sodium content of unfortified DHM was 102.0 mg/L (4.4 mEq). Because <1% of bovine-fortified samples met the recommended sodium content, infants born preterm who are fed predominantly DHM likely require additional sodium.