Bacteriological, biochemical, and immunological properties of colostrum and mature milk from mothers of extremely preterm infants

Factors Associated with Low Volumes of Mother's Own Milk at Neonatal Intensive Care Unit Discharge of Very Low Birth Weight Infants-a Cohort Study

Background: Mother's own milk (MOM) provides health benefits for infants with very low birth weight (VLBW). This study aimed to describe the incidence and factors associated with low volumes of MOM (<50% of total diet volume) at discharge for VLBW infants. Methods: A prospective cohort study of infants with VLBW and gestational age of <30 weeks, who survived to discharge and had no contraindication to MOM. We conducted bivariate analyses to investigate associations with the volume of MOM at discharge, using chi-square, t, and Mann-Whitney tests. All p-value analyses were two-tailed. The variables significantly associated with "low volumes of MOM" entered the multivariable analysis. Univariate and multivariate relative risk (confidence interval [CI] 95%) estimates were obtained from Poisson regression with a robust estimate of variance and controlled by the length of hospital stay. Results: Of 414 infants included and followed until discharge, 32.9% (n = 136) received less than 50% of the total daily volume of MOM. This outcome was associated with gestational age <28 weeks, lower birth weight, multiple births, developing bronchopulmonary dysplasia, and longer lengths of stay. After Poisson regression, low volumes of MOM at discharge were associated only with being born multiples (RR 2.01; CI 95% 1.53-2.64, p < 0.001) and with longer length of stay (RR 1.07; CI 95% 1.01-1.14, p = 0.01). Conclusions: Most VLBW infants were discharged home receiving predominantly MOM. Each neonatal intensive care unit (NICU) should acknowledge which clinical characteristics of mothers and VLBW infants are associated with difficulties maintaining MOM volumes until discharge.

Human Milk Microbiome-A Review of Scientific Reports

One of the most important bioactive components of breast milk are free breast milk oligosaccharides, which are a source of energy for commensal intestinal microorganisms, stimulating the growth of Bifidobacterium, Lactobacillus, and Bacteroides in a child's digestive tract. There is some evidence that maternal, perinatal, and environmental-cultural factors influence the modulation of the breast milk microbiome. This review summarizes research that has examined the composition of the breast milk microbiome and the factors that may influence it. The manuscript highlights the potential importance of the breast milk microbiome for the future development and health of children. The origin of bacteria in breast milk is thought to include the mother's digestive tract (entero-mammary tract), bacterial exposure to the breast during breastfeeding, and the retrograde flow of breast milk from the infant's mouth to the woman's milk ducts. Unfortunately, despite increasingly more precise methods for assessing microorganisms in human milk, the topic of the human milk microbiome is still quite limited and requires scientific research that takes into account various conditions.

Understanding the Immunological Quality of Breast Milk in Maternal Overweight and Obesity

Maternal obesity, affecting many pregnant women globally, not only poses immediate health risks but also modulates breast milk composition. Obesity is linked to inflammation and oxidative stress, impacting breast milk's immune properties. This paper explores the intricate relationship between maternal metabolic disorders, such as obesity, and breast milk's immunological components. We conducted a thorough search for original and review articles published until 17 October 2023 in the PUBMED/Scopus database. This search included several terms related to human breast milk, immunological properties, and obesity. Articles were selected with the consensus of all authors. Maternal metabolic disorders have discernible effects on the composition of immune-related components in breast milk, such as immunoglobulins, lactoferrin, leptin, ghrelin, adiponectin, C-reactive protein, growth factors, extracellular vesicles, and lymphocytes. These changes in breast milk composition can significantly impact the newborn's immune system, with potential long-term health implications beyond the immediate postnatal period. Maternal metabolic health is a critical factor in shaping the health trajectory of the neonate through breastfeeding, although the full advantages of breastfeeding for children of mothers with obesity remain uncertain. Ongoing research aims to understand and unravel these links.

Inflammatory Markers in Mother's Own Milk and Infant Stool of Very Low Birthweight Infants

BACKGROUND

Mother's breastmilk is the gold standard for feeding preterm infants. Preterm delivery may be precipitated by inflammatory maternal states, but little is known about milk cytokine profiles and how they correlate with markers of infant gut inflammation (i.e., stool calprotectin) in this vulnerable population.

RESEARCH AIM

To assess cytokines and inflammatory markers in milk from parents of very preterm infants over time as well as correlations between milk and infant's stool calprotectin.

METHOD

This is a secondary analysis of milk samples collected during OptiMoM, a triple-blind randomized clinical trial of infants born < 1250 g (NCT02137473). Longitudinally collected samples were analyzed for cytokines, choline, and inflammatory markers (C-reactive protein [CRP], IFN-γ, IL-10, IL-1β, IL-1ra, IL-6, IL-8, TNF-α). Infant stools were collected for longitudinal calprotectin analysis. Generalized estimating equations quantified longitudinal profiles of milk markers and stool calprotectin, their associations, and the correlation between free choline and C-reactive protein over follow-up.

RESULT

Participants included 92 parents and infants (median weeks of gestation 27.3, median birth weight 845 g, and prevalence of male infants 45%). In all, 212 milk samples and 94 corresponding stool calprotectin levels were collected 1-11 weeks postpartum. C-reactive protein was present in much higher concentrations than other markers, and was highest in Week 1 postpartum. It decreased over time. IL-8 and free choline also changed over time while other markers did not. There was no correlation between any milk markers and stool calprotectin.

CONCLUSION

Milk from mothers of very preterm infants has detectable inflammatory markers, some of which change over time. Research is needed to determine if infant outcomes are associated with these markers.

Human milk immune factors, maternal nutritional status, and infant sex: The INSPIRE study

OBJECTIVES

Breastfeeding is an energetically costly and intense form of human parental investment, providing sole-source nutrition in early infancy and bioactive components, including immune factors. Given the energetic cost of lactation, milk factors may be subject to tradeoffs, and variation in concentrations have been explored utilizing the Trivers-Willard hypothesis. As human milk immune factors are critical to developing immune system and protect infants against pathogens, we tested whether concentrations of milk immune factors (IgA, IgM, IgG, EGF, TGFβ2, and IL-10) vary in response to infant sex and maternal condition (proxied by maternal diet diversity [DD] and body mass index [BMI]) as posited in the Trivers-Willard hypothesis and consider the application of the hypothesis to milk composition.

METHODS

We analyzed concentrations of immune factors in 358 milk samples collected from women residing in 10 international sites using linear mixed-effects models to test for an interaction between maternal condition, including population as a random effect and infant age and maternal age as fixed effects.

RESULTS

IgG concentrations were significantly lower in milk produced by women consuming diets with low diversity with male infants than those with female infants. No other significant associations were identified.

CONCLUSIONS

IgG concentrations were related to infant sex and maternal diet diversity, providing minimal support for the hypothesis. Given the lack of associations across other select immune factors, results suggest that the Trivers-Willard hypothesis may not be broadly applied to human milk immune factors as a measure of maternal investment, which are likely buffered against perturbations in maternal condition.

The impact on colostrum oxidative stress, cytokines, and immune cells composition after SARS-CoV-2 infection during pregnancy

Background

Limited data are available regarding the differences between immunological, biochemical, and cellular contents of human colostrum following maternal infection during pregnancy with coronavirus 2 disease (COVID-19).

Objective

To investigate whether maternal COVID-19 infection may affect immunological, biochemical, and cellular contents of human colostrum.

Methods

Using a case-control study design, we collected colostrum from 14 lactating women with a previous diagnosis of COVID-19 during pregnancy and 12 without a clear diagnosis during September 2020 to May 2021. Colostrum samples were analysed for some enzymes and non-enzymatic oxidative stress markers (SOD, CAT, GPx, MDA, GSH, GSSG, H2O2, MPO) and for IL-1β, IL-6, tumour necrosis factor (TNF)-α, protein induced by interferon gamma (IP)-10, IL-8, IFN-λ1, IL12p70, IFN-α2, IFN-λ2/3, granulocyte macrophage colony stimulating factor (GM-CSF), IFN-β, IL-10 and IFN-γ, along with IgA and IgG for the SARS-CoV-2 S protein. We perform immunophenotyping to assess the frequency of different cell types in the colostrum.

Results

Colostrum from the COVID-19 symptomatic group in pregnancy contained reduced levels of H2O2, IFN-α2, and GM-CSF. This group had higher levels of GSH, and both NK cell subtypes CD3-CD56brightCD16-CD27+IFN-γ+ and CD3-CD56dimCD16+CD27- were also increased.

Conclusion

The present results reinforce the protective role of colostrum even in the case of mild SARS-Cov-2 infection, in addition to demonstrating how adaptive the composition of colostrum is after infections. It also supports the recommendation to encourage lactating women to continue breastfeeding after COVID-19 illness.

Lactation time influences the composition of Bifidobacterium and Lactobacillus at species level in human breast milk

Human breast milk is a source of microorganisms for infants that play an important role in building infant gut health and immunity. The bacterial composition in human breast milk is influenced by lactation time. This study aimed to investigate the influence of lactation time on bacteria in breast milk at the genus level and the species levels of Bifidobacterium and Lactobacillus on days 2-4, 8, 14, and 30. Eighteen individuals were recruited and 60 milk samples were collected. The 16S rRNA gene, and the bifidobacterial groEL and lactobacilli groEL genes were used for amplicon sequencing. The results revealed that the alpha diversities of colostrum and transition 1 (day 8) milk were lower than that of transition 2 (day 14) and mature milk. PCoA analysis showed that bacterial composition in colostrum and transition 1 milk differed from transition 2 and mature milk. A lower relative abundance of Blautia was found in colostrum and transition 1 milk compared with mature milk and lower abundances of Ruminococcus, Dorea, and Escherichia-Shigella were found in transition 1 compared with mature milk. Bifidobacterium ruminantium, Limosilactobacillus mucosae, and Ligilactobacillus ruminis were the predominant species across all four lactation stages, while Bifidobacterium bifidum was lower in transition 1, and Bifidobacterium pseudocatenulatum and Bifidobacterium pseudolongum were higher in transition 1 milk. This study indicated that the bacterial composition in colostrum was more similar to that of transition 1 milk, whereas the bacterial community in transition 2 milk was similar to that of mature milk which suggests that bacterial composition in human breast milk shows stage-specific signatures even within a short period at both genus level and Bifidobacterium and Lactobacillus species levels, providing insights into probiotic supplementation for the nursing mother.

Changes in Antisecretory Factor in Human Milk During the Postpartum and Length of Gestation

BACKGROUND

Preterm infants are more susceptible to inflammatory complications than term infants. Human milk contains numerous bioactive components protecting the newborn infant. Antisecretory factor, a protein regulating secretory and inflammatory processes by complex binding with complement factors, is present in human milk.

RESEARCH AIMS

To describe antisecretory factor (1) in mother's own milk in term and preterm infants; and (2) in donor milk before and after Holder pasteurization.

METHODS

The study was prospective, longitudinal, explorative, and descriptive. Antisecretory factor-compleasome was determined using sandwich enzyme-linked immunosorbent assay in longitudinal human milk samples over 12 weeks from mothers (N = 87) of term (n = 41) and of preterm (n = 46) infants and 20 anonymized donor human milk samples before and after Holder pasteurization.

RESULTS

Antisecretory factor-compleasome was overall higher in colostrum versus mature milk (p < .001) and no difference was found in term or preterm colostrum (p = .82). In mature milk, compleasome was higher and more variable in the preterm group (p = .01). After Holder pasteurization, compleasome levels increased (p < .001).

CONCLUSION

Antisecretory factor followed the pattern of other immunological factors with high levels in colostrum. After preterm birth, levels of antisecretory factor were higher and more variable in mature milk. Holder pasteurization did not degrade antisecretory factor, indicating preserved anti-inflammatory properties in donor human milk.

The Trajectory of Expressed Colostrum Volume in the First 48 Hours Postpartum: An Observational Study

Objective: Colostrum, the first form of human milk, is strongly encouraged for infants due to its benefits. During the early postpartum (PP) period, the secreted colostrum volume can be minimal, causing concerns among mothers about sufficient milk supply. Few studies have examined temporal changes in the colostrum. This study aimed to elucidate the trajectory of expressed colostrum volume in the first 48 hours after delivery. Materials and Methods: This was a cross-sectional observational study performed at Kagawa National Children's Hospital. One hundred five mothers who did not directly breastfeed in the first 48 hours after delivery were enrolled in the study. Well-trained midwives instructed the mothers on how to express human milk, and mothers started to express as soon as possible after delivery. Mothers were advised to express human milk every 3 hours, and the milk volume was measured. Results: Within 3 hours PP, 60% of mothers expressed milk, and the median frequency of expression was 14 (interquartile range, 11-16) times in the first 48 hours. At 0-3 and 3-6 hours PP, the volume of initially expressed milk was 0.4 (0.0-2.0) mL and 1.0 (0.0-6.0) mL, respectively. Subsequently, milk volume decreased. The volume remained low until 30 hours PP and increased dramatically; this phenomenon is termed secretory activation, which began later in primiparous women than in multiparous women. Conclusion: The decline in expressed milk volume during the early PP period caused concern among mothers. Therefore, mothers should be informed of the PP trajectory of human milk volume.

Myo-Inositol Supplementation in Suckling Rats Protects against Adverse Programming Outcomes on Hypothalamic Structure Caused by Mild Gestational Calorie Restriction, Partially Comparable to Leptin Effects

We studied whether myo-inositol supplementation throughout lactation, alone and combined with leptin, may reverse detrimental effects on hypothalamic structure and function caused by gestational calorie gestation (CR) in rats. Candidate early transcript-based biomarkers of metabolic health in peripheral blood mononuclear cells (PBMC) were also studied. Offspring of dams exposed to 25% gestational CR and supplemented during lactation with physiological doses of leptin (CR-L), myo-inositol (CR-M), the combination (CR-LM), or the vehicle (CR-V) as well as control rats (CON-V) were followed and sacrificed at postnatal day 25. Myo-inositol and the combination increased the number of neurons in arcuate nucleus (ARC) (only in females) and paraventricular nucleus, and myo-inositol (alone) restored the number of αMSH⁺ neurons in ARC. Hypothalamic mRNA levels of Lepr in CR-M and Insr in CR-M and CR-LM males were higher than in CR-V and CON-V, respectively. In PBMC, increased expression levels of Lrp11 and Gls in CR-V were partially normalized in all supplemented groups (but only in males for Gls). Therefore, myo-inositol supplementation throughout lactation, alone and combined with leptin, reverts programmed alterations by fetal undernutrition on hypothalamic structure and gene expression of potential early biomarkers of metabolic health in PBMC, which might be attributed, in part, to increased leptin sensitivity.

Does oropharyngeal administration of colostrum reduce morbidity and mortality in very preterm infants? A randomised parallel-group controlled trial

AIM

To evaluate whether a strategy of oropharyngeal administration of colostrum reduces morbidity and mortality in very preterm infants.

METHODS

A total of 260 neonates with gestational age 26-31 weeks at birth were randomised between August 2017 and August 2018 to receive 0.2 mL of human milk or placebo respectively via the oropharyngeal route, beginning within 24 h after birth, and continued every 3 h until oral feeds were initiated. The primary outcome was a composite of death, late-onset sepsis (LOS) or necrotising enterocolitis (NEC) in the neonatal period.

RESULTS

A total of 260 infants (mean gestational age 29.5 weeks, and mean birthweight 1201.7 g) were included in the primary analysis. The composite primary outcome occurred in 43 (33.6%) infants in the colostrum group and 38 infants (29.7%) in the placebo group, and the difference was not statistically significant (P = 0.50). Secondary outcomes including the incidence of death, NEC, LOS, probable sepsis, intraventricular haemorrhage, ventilator-associated pneumonia, retinopathy of prematurity, bronchopulmonary dysplasia, time to full feeds, time to regain birthweight, duration of hospital stay and survival to 6 months without major neurosensory impairment were also comparable between the two groups.

CONCLUSION

A strategy of oropharyngeal administration of colostrum in very preterm and extremely preterm neonates did not decrease the composite primary outcome of death, LOS or NEC. This finding is consistent with most published literature in the area.

Immediate Pre-Partum SARS-CoV-2 Status and Immune Profiling of Breastmilk: A Case-Control Study

Objetive

To address the prevalence of SARS-CoV-2 and the evolutionary profile of immune compounds in breastmilk of positive mothers according to time and disease state.

Methods

Forty-five women with term pregnancies with confirmed non-severe SARS-CoV-2 infection (case group), and 96 SARS-CoV-2 negative women in identical conditions (control group) were approached, using consecutive sample. Weekly (1st to 5th week postpartum) reverse transcription polymerase chain reaction (RT-PCR) in nasopharyngeal swabs (cases) and breastmilk (cases and controls) were obtained. Concentration of cytokines, chemokines, and growth factors in breastmilk (cases and controls) were determined at 1st and 5th week post-partum.

Results

Thirty-seven (study group) and 45 (control group) women were enrolled. Symptomatic infection occurred in 56.8% of women in the study group (48% fever, 48% anosmia, 43% cough). SARS-CoV-2 RNA was not found in breastmilk samples. Concentrations of cytokines (IFN-γ, IL-1ra, IL-4, IL-6, IL-9, IL-13, and TNF-α) chemokines (eotaxin, IP-10, MIP-1α, and RANTES) and growth factors (FGF, GM-CSF, IL7, and PDGF-BB) were higher in breastmilk of the study compared with the control group at 1st week postpartum. Immune compounds concentrations decreased on time, particularly in the control group milk samples. Time of nasopharyngeal swab to become negative influenced the immune compound concentration pattern. Severity of disease (symptomatic or asymptomatic infection) did not affect the immunological profile in breast milk.

Conclusions

This study confirms no viral RNA and a distinct immunological profile in breastmilk according to mother’s SARS-CoV-2 status. Additional studies should address whether these findings indicate efficient reaction against SARS-CoV-2 infection, which might be suitable to protect the recipient child.

The Breast Milk Immunoglobulinome

Breast milk components contribute to the infant’s immune development and protection, and among other immune factors, immunoglobulins (Igs) are the most studied. The presence of IgA in milk has been known for a long time; however, less information is available about the presence of other Igs such as IgM, IgG, and their subtypes (IgG1, IgG2, IgG3, and IgG4) or even IgE or IgD. The total Ig concentration and profile will change during the course of lactation; however, there is a great variability among studies due to several variables that limit establishing a clear pattern. In this context, the aim of this review was firstly to shed light on the Ig concentration in breast milk based on scientific evidence and secondly to study the main factors contributing to such variability. A search strategy provided only 75 studies with the prespecified eligibility criteria. The concentrations and proportions found have been established based on the intrinsic factors of the study—such as the sampling time and quantification technique—as well as participant-dependent factors, such as lifestyle and environment. All these factors contribute to the variability of the immunoglobulinome described in the literature and should be carefully addressed for further well-designed studies and data interpretation.

Human Breast Milk: Bioactive Components, from Stem Cells to Health Outcomes

PURPOSE OF REVIEW

Breast milk (BM) is a peculiar fluid owing unique properties and resulting the ideal food during early neonatal period. As widely known, it can improve the outcome of both neonate and lactating mother, influencing their whole life. BM is characterized by several beneficial components; among these, a great role is played by BM own and specific microbiome, deeply investigated in many studies. Moreover, the use of metabolomics in BM analysis allowed a better characterization of its metabolic pathways that vary according to lactation stage and neonatal gestational age. The aim of this review is to describe growth factors, cytokines, immunity mediators, and stem cells (SCs) contained in BM and investigate their functions and effects on neonatal outcome, especially focusing on immuno- and neurodevelopment.

RECENT FINDINGS

We evaluated recent and updated literature on this field. The article that we analyzed to write this review have been found in MEDLINE using breast milk-derived stem cells, biofactors, growth factors, breastfeeding-related outcomes, neurodevelopment, and neonatal immunological system as keywords. Discovering and characterizing BM components could result very useful to clarify the pathophysiology of their influence on neonatal growth and even to improve artificial formulations' composition. Moreover, since SCs abilities and their involvement in the development of several diseases, they could help to discover specific targets for new therapies. It could be useful to characterize BM-derived SC markers, properties, and variations during lactation stages, to understand their potential role in therapeutic applications, since they could be noninvasively isolated from BM. More studies will help to describe more in detail the characteristics of mother-to-child communication through breastfeeding and its potential role in the next future.

Frozen Mother's Own Milk Can Be Used Effectively to Personalize Donor Human Milk

Feeding preterm infants mother's own milk (MOM) lowers rates of sepsis, decreases necrotizing enterocolitis, and shortens hospital stay. In the absence of freshly expressed MOM, frozen MOM (FMOM) is provided. When MOM is unavailable, preterm infants are often fed pasteurized donor human milk (DHM), rendering it devoid of beneficial bacteria. We have previously reported that when MOM is inoculated into DHM to restore the live microbiota [restored milk (RM)], a similar microbial diversity to MOM can be achieved. Yet, it is unknown if a similar diversity to MOM can be obtained when FMOM is inoculated into DHM. The goal of this study was to determine whether a similar microbial composition to MOM could be obtained when FMOM is used to personalize DHM. To this end, a fresh sample of MOM was obtained and divided into fresh and frozen fractions. MOM and FMOM were inoculated into DHM at different dilutions: MOM/FMOM 10% (RM/FRM10) and MOM/FMOM 30% (RM/FRM30) and incubated at 37°C. At different timepoints, culture-dependent and culture-independent techniques were performed. Similar microbiota expansion and alpha diversity were observed in MOM, RM10, and RM30 whether fresh or frozen milk was used as the inoculum. To evaluate if microbial expansion would result in an abnormal activation on the innate immune system, Caco-2 epithelial cells were exposed to RM/FRM to compare interleukin 8 levels with Caco-2 cells exposed to MOM or DHM. It was found that RM samples did not elicit a significant increase in IL-8 levels when compared to MOM or FMOM. These results suggest that FMOM can be used to inoculate DHM if fresh MOM is unavailable or limited in supply, allowing both fresh MOM and FMOM to be viable options in a microbial restoration strategy.

High-Temperature Short-Time and Holder Pasteurization of Donor Milk: Impact on Milk Composition

Holder pasteurization (HoP; 62.5 °C, 30 min) is commonly used to ensure the microbiological safety of donor human milk (DHM) but diminishes its nutritional properties. A high-temperature short-time (HTST) system was designed as an alternative for human milk banks. The objective of this study was to evaluate the effect of this HTST system on different nutrients and the bile salt stimulated lipase (BSSL) activity of DHM. DHM was processed in the HTST system and by standard HoP. Macronutrients were measured with a mid-infrared analyzer. Lactose, glucose, myo-inositol, vitamins and lipids were assayed using chromatographic techniques. BSSL activity was determined using a kit. The duration of HTST treatment had a greater influence on the nutrient composition of DHM than did the tested temperature. The lactose concentration and the percentage of phospholipids and PUFAs were higher in HTST-treated than in raw DHM, while the fat concentration and the percentage of monoacylglycerides and SFAs were lower. Other nutrients did not change after HTST processing. The retained BSSL activity was higher after short HTST treatment than that following HoP. Overall, HTST treatment resulted in better preservation of the nutritional quality of DHM than HoP because relevant thermosensitive components (phospholipids, PUFAs, and BSSL) were less affected.

Dose-dependent effect of human milk on Bronchopulmonary dysplasia in very low birth weight infants

Background and aim

Human milk has potential protective effects against bronchopulmonary dysplasia (BPD). However, studies on the association between the dose of human milk and BPD in China are limited. This study aimed to evaluate the dose-dependent effects of human milk on BPD and other neonatal morbidities in very low birth weight (VLBW) infants.

Methods

This retrospective cohort study of preterm infants was conducted on preterm infants of gestational age ≤ 34 weeks and birth weight < 1500 g admitted to the multicenter clinical research database for breastfeeding quality improvement in Jiangsu province. The multivariate analysis was performed to compare the effect outcomes of daily graded doses [1–24 mL/(kg · day), 25–49 mL/(kg · day), and ≥ 50 mL/(kg · day) of body weight] of human milk on neonatal outcomes throughout the first 4 weeks of life versus a reference group receiving no human milk. The models were adjusted for potential confounding variables.

Results

Of 964 included infants, 279 (28.9%) received exclusive preterm formula, 128 (13.3%) received 1–24 ml/(kg · day), 139 (14.4%) received 25–49 ml/(kg · day), and 418 (43.4%) received ≥50 ml/(kg · day) human milk for the first 4 weeks of life. Compared with infants receiving exclusive formula, those receiving the highest volume of human milk daily [≥50 mL/(kg · day)] had lower incidences of BPD [27.5% in ≥50 mL/(kg · day) vs 40.1% in 0 mL/(kg · day) human milk, P = 0.001)], moderate and severe BPD [8.9% in ≥50 mL/(kg · day) vs 16.1% in 0 mL/(kg · day), P = 0.004], necrotizing enterocolitis [NEC; 3.8% in ≥50 mL/(kg · day) vs 10.8% in 0 mL/(kg · day), P = 0.001], late-onset sepsis [LOS; 9.3% in ≥50 mL/(kg · day) vs 19.7% in 0 mL/(kg · day), P <0.01], and extrauterine growth retardation [EUGR; 38.5% in ≥50 mL/(kg · day) vs 57.6% in 0 mL/(kg · day), P <0.01)]. The logistic regression indicated that those receiving ≥50 ml/kg · day human milk had lower odds of BPD [adjusted odds ratio (AOR) 0.453; 95% confidence interval (CI): 0.309, 0.666], moderate and severe BPD (AOR 0.430; 95% CI: 0.249, 0.742), NEC (AOR 0.314; 95% CI: 0.162, 0. 607), LOS (AOR 0.420; 95% CI: 0.263, 0.673), and EUGR (AOR 0.685; 95% CI: 0.479, 0.979).

Conclusions

A daily threshold amount of ≥50 ml/(kg · day) human milk in the first 4 weeks of life was associated with lower incidence of BPD as well as NEC, LOS, and EUGR in VLBW infants.

Trial registration

ClinicalTrials.gov Identifier: NCT03453502. Registration date: March 5, 2018. This study was retrospectively registered.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12887-020-02394-1.

Investigation of the Defatted Colostrum 1H-NMR Metabolomics Profile of Gilts and Multiparous Sows and Its Relationship with Litter Performance

Simple Summary

Swine colostrum quality and quantity can influence the growth and survival of piglets and contribute to the differences in productive traits of gilts and multiparous sows. The aim of the study was to characterize the soluble metabolomics profile of defatted colostrum of sows at different parity number (PA) and to correlate the metabolomics profile with the colostrum Brix percentage as an estimate measure of immunoglobulin G (IgG) concentration and sow productive traits. The metabolomics profile of colostrum reveals a slight influence of parity, which can influence the quantity of specific metabolites including glycine and lactose. Specific metabolites including lactose creatine, myo-inositol, and O-phosphocholine partially explain the colostrum IgG Brix percentage. Sows’ productive traits performance, including the litter weight at birth and piglets’ mortality, can be influenced by the metabolites related to a sow’s metabolic condition. Increasing knowledge on the interplay between colostrum composition and litter performance can pave the way to define management strategies to provide piglets with good-quality colostrum, improving welfare and economic sustainability of pig rearing by reducing piglet mortality.

Abstract

The aim of the study was to characterize the soluble metabolomics profile of defatted colostrum of sows at different parity number (PA) and to correlate the metabolomics profile with the Brix percentage estimate of colostrum immunoglobulin G (IgG) and sow productive traits. A total of 96 Meidam (crossbreed Large White × Meishan) sows of PA from 1–4 (PA1: 28; PA2:26; PA3:12; PA4:26) were included, and their productive traits were recorded at 10 days post-farrowing. Colostrum IgG was quantified using a Brix refractometer, and metabolomics profile was assessed using ¹H-NMR spectroscopy. Sows’ PA slightly influenced the metabolomics profile of colostrum. lactose and glycine were higher in PA1 compared with PA4 (p 0.05) and N-acetylglucosamine (GlcNAc) tended to be higher in PA2 than PA3 and PA4 (p < 0.10). The Brix percentage of IgG was negatively associated with lactose and positively with creatine, myo-inositol, and O-phosphocholine (p < 0.05). Taurine was positively related to litter weight at birth. GlcNAc and myo-inositol were linked to piglet mortality at day 10 with a negative and positive trend, respectively. In conclusion, colostrum of gilts and multiparous sows had a similar metabolomics profile. Specific metabolites contributed to explanation of the variability in colostrum Brix percentage estimate of IgG concentration and the sows’ productive performance.

Cross talk of vascular endothelial growth factor and neurotrophins in mammary gland development

During the period of lactation, there is extensive growth and development of the mammary gland in order to fulfil the increased demands of milk for the growing infant. Angiogenesis plays a key role in alveolar development and facilitates optimal milk production. Vascular endothelial growth factor (VEGF) is one of the key growth factors regulating angiogenesis in mammary gland. Apart from VEGF, neurotrophins are also known to regulate angiogenesis through direct or indirect mechanisms. Few studies have demonstrated mRNA levels of neurotrophins and their receptors in mammary gland both in humans and rodents. A cross talk between VEGF and neurotrophins has been described in placental development. The enteric and central nervous system are not fully developed at birth, making it imperative to have appropriate levels of angiogenic factors and neurotrophins during postnatal period. The current review summarises studies which describe the role of neurotrophins and angiogenic factors in the mammary gland development.

Staphylococcus epidermidis sepsis induces hypercoagulability in preterm pigs

Gram positive bacteria are a cause of sepsis in human preterm infants, and associates with high mortality and hemostatic dysfunction. It is unknown whether bovine colostrum may protect against sepsis and prevent hemostatic dysfunction. The current study was part of an overall sepsis study investigating Staphylococcus epidermidis (SE) induced sepsis in premature pigs including investigation of the effect of feeding bovine colostrum. The specific hypothesis of this study was that the hemostatic response would be hypercoagulable in septic pigs compared to non-infected controls, and that feeding bovine colostrum would increase the hypercoagulant response. Thromboelastography, activated partial thromboplastin time, prothrombin time and fibrinogen concentration were characterized in SE infected pigs, SE infected pigs fed bovine colostrum, and uninfected controls. All pigs were followed for 24 h. In addition, the same parameters were evaluated in a group of premature pigs and a group of full born pigs all followed for 11 days. SE septic premature pigs were characterized by increased clot strength and decreased fibrinolysis, significantly low platelet count and high fibrinogen concentration. Feeding bovine colostrum did not affect the hemostatic response. Compared to full born pigs, preterm newborn pigs demonstrated reduced clot strength, prolonged prothrombin time and low fibrinogen concentration. In all pigs, the fibrinogen concentration increased 11 days post-partum. To conclude, SE induced sepsis in premature pigs resulted in hypercoagulability. Bovine colostrum did not mitigate the hemostatic response. A hypocoagulable hemostatic response was present in healthy preterm pigs compared to full born pigs, similar to previous reports in infants.

Bifidobacterium Supplementation of Colostrum and Breast Milk Enhances Weight Gain and Metabolic Responses Associated with Microbiota Establishment in Very-Preterm Infants

Background

Postnatal growth restriction in very-preterm infants (VPIs) may have long-lasting effects. Recent evidence suggests that developmental problems in VPIs are related to abnormalities in intestinal microbial communities.

Objective

To investigate the effect on growth outcomes in VPIs of supplementation with Bifidobacterium along with mother's colostrum and breast milk.

Methods

A randomized controlled study was performed on 35 VPIs, born between 24 and 31 weeks of gestation with birth weights <1,500 g. The patients received either daily Bifidobacterium breve supplementation (Bifid group) or vehicle supplement only (placebo group). Parenteral nutrition was initiated with glucose, amino acids, and fatty acids for all of the infants soon after birth. Each infant received their own mother's colostrum within 24 h of birth, and breast milk on subsequent days. Fecal bacteria, organic acids, pH, bile acids, and plasma fatty acids were analyzed.

Results

Seventeen infants were allocated to the Bifid group and 18 to the placebo group; the birth weights and gestational ages did not differ significantly between the two groups. Compared to the placebo group, the Bifid group showed significantly greater and earlier weight gain by 8 weeks; significantly higher total fecal bacterial counts, including bifidobacteria; higher levels of total fecal short-chain fatty acids and nominally (but not significantly) higher concentrations of plasma n−3 fatty acids; and lower levels of total fecal bile acid.

Conclusions

Bifidobacterial supplementation of maternal colostrum and breast milk yielded the establishment of a beneficial microbiota profile, leading to favorable metabolic responses that appeared to provide improved growth in VPIs.

The Preterm Gut Microbiota: An Inconspicuous Challenge in Nutritional Neonatal Care

The nutritional requirements of preterm infants are unique and challenging to meet in neonatal care, yet crucial for their growth, development and health. Normally, the gut microbiota has distinct metabolic capacities, making their role in metabolism of dietary components indispensable. In preterm infants, variation in microbiota composition is introduced while facing a unique set of environmental conditions. However, the effect of such variation on the microbiota's metabolic capacity and on the preterm infant's growth and development remains unresolved. In this review, we will provide a holistic overview on the development of the preterm gut microbiota and the unique environmental conditions contributing to this, in addition to maturation of the gastrointestinal tract and immune system in preterm infants. The role of prematurity, as well as the role of human milk, in the developmental processes is emphasized. Current research stresses the early life gut microbiota as cornerstone for simultaneous development of the gastrointestinal tract and immune system. Besides that, literature provides clues that prematurity affects growth and development. As such, this review is concluded with our hypothesis that prematurity of the gut microbiota may be an inconspicuous clinical challenge in achieving optimal feeding besides traditional challenges, such as preterm breast milk composition, high nutritional requirements and immaturity of the gastrointestinal tract and immune system. A better understanding of the metabolic capacity of the gut microbiota and its impact on gut and immune maturation in preterm infants could complement current feeding regimens in future neonatal care and thereby facilitate growth, development and health in preterm infants.

Oropharyngeal Mother's Milk: State of the Science and Influence on Necrotizing Enterocolitis

Oropharyngeal administration of mother's own milk-placing drops of milk directly onto the neonate's oral mucosa-may serve to (ex utero) mimic the protective effects of amniotic fluid for the extremely low birth weight infant; providing protection against necrotizing enterocolitis. This article presents current evidence to support biological plausibility for the use of OroPharyngeal Therapy with Mother's Own Milk (OPT-MOM) as an immunomodulatory therapy; an adjunct to enteral feeds of mother's milk administered via a nasogastric or orogastric tube. Current methods and techniques are reviewed, published evidence to guide clinical practice will be presented, and controversies in practice will be addressed.

Closing the Gap Between Recommended and Actual Human Milk Use for Fragile Infants: What Will It Take to Overcome Disparities?

This article describes the components of human milk and their value to reduce risk for necrotizing enterocolitis, disparities in access to human milk, potential relationships to care practices within the neonatal intensive care unit, and ways to overcome the disparity.

Immunonutrition for Preterm Infants

Care and outcomes for very preterm infants continue to improve, but important causes of mortality and acute and long-term morbidity associated with prolonged hospitalisation remain. Necrotising enterocolitis (NEC) and late-onset infection have emerged as the major causes of death beyond the early neonatal period and of neurodisability in very preterm infants. Although the pathogenesis of these conditions is incompletely understood, it appears to be related to the content and mode of delivery of the enteral diet, particularly the impact of immunonutrients from human breast milk on the microbial and metabolic balance within the immature intestine. Evidence exists to support investment in measures to help mothers to express breast milk as the primary source of nutrition for their very preterm infants. In the absence of maternal milk, pasteurised donor breast milk provides protection against NEC, but its nutritive adequacy is not clear and its cost-effectiveness is uncertain. Supplementation with individual immunonutrients, including immunoglobulins and lactoferrin, has not been shown to be effective in preventing NEC or infection in randomised controlled trials. The evidence base for prebiotics and probiotics is stronger, but concerns exist about the choice, safety and availability of formulations. Other strategies - including avoidance of drugs such as gastric acid suppressants that compromise innate immunity, as well as evidence-based progressive feeding strategies that reduce exposure to invasive interventions - are emerging as key components of care packages to reduce the burden of NEC, infection and associated growth and developmental faltering for very preterm infants.

Strategies for the Preservation, Restoration and Modulation of the Human Milk Microbiota. Implications for Human Milk Banks and Neonatal Intensive Care Units

Studies carried in the last years have revealed that human milk contains a site-specific microbiota and constitutes a source of potentially beneficial bacteria to the infant gut. Once in the infant gut, these bacteria contribute to the assembly of a physiological gut microbiota and may play several functions, contributing to infant metabolism, protection against infections, immunomodulation or neuromodulation. Many preterm neonates are fed with pasteurized donor's human milk (DHM) or formula and, therefore, are devoid of contact with human milk microbes. As a consequence, new strategies are required to allow the exposition of a higher number of preterm infants to the human milk microbiota early in life. The first strategy would be to promote and to increase the use of own mother's milk (OMM) in Neonatal Intensive Care Units (NICUs). Even small quantities of OMM can be very valuable since they would be added to DHM in order to microbiologically "customize" it. When OMM is not available, a better screening of donor women, including routine cytomegalovirus (CMV) screening of milk, may help to avoid the pasteurization of the milk provided by, at least, a relevant proportion of donors. Finally, when pasteurized DHM or formula are the only feeding option, their supplementation with probiotic bacteria isolated from human milk, such as lactic acid bacteria or bifidobacteria, may be an alternative to try to restore a human milk-like microbiota before feeding the babies. In the future, the design of human milk bacterial consortia (minimal human milk microbiotas), including well characterized strains representative of a healthy human milk microbiota, may be an attractive strategy to provide a complex mix of strains specifically tailored to this target population.

Facilitating Colostrum Collection by Hospitalized Women in the Early Postpartum Period for Infant Trophic Feeding and Oral Immune Therapy

Administration of colostrum for early trophic feedings and colostrum oral immune therapy for neonates in the NICU is essential to enhance gut maturation and lower risk of infections. However, it is often difficult for women to collect early colostrum because of its thick viscosity and low volume. Women may be unable to sit upright during pumping sessions because of postsurgical pain, acute or chronic illness, or birth complications and may need assistance. In this article, we describe specific techniques that providers can use to help women to collect colostrum when they are unable to accomplish collection on their own. Helping women collect and administer colostrum to their neonates in the NICU may engage and motivate them to continue to pump and provide breast milk for their hospitalized neonates.

Effects of lactoferrin on neonatal pathogens and Bifidobacterium breve in human breast milk

Supplementation with probiotics in preterm infants reduces necrotizing enterocolitis and sepsis. Bovine lactoferrin is a promising supplement that may further reduce disease burden, but its effects on probiotic bacteria in human breast milk has not been evaluated. We aimed to characterise the antimicrobial activity of bovine and human lactoferrin in human breast milk against probiotics and typical neonatal sepsis pathogens. Lactoferrin levels were determined by enzyme linked immunosorbent assay in fresh and pasteurised human breast milk. The neonatal pathogens Staphylococcus epidermidis and Escherichia coli, and the probiotic Bifidobacterium breve strain M-16V were cultured in human breast milk or infant formula in the presence or absence of clinically relevant doses of bovine or human lactoferrin. Standard microbiological methods were used to determine the effects of lactoferrin on bacterial growth. Unpasteurised human breast milk contained significantly higher lactoferrin levels and resulted in superior inhibition of pathogenic bacterial growth compared to infant formula and pasteurised human breast milk. Human lactoferrin was significantly more effective at inhibiting bacterial growth, when compared to bovine lactoferrin. Supplementation with human lactoferrin or high dose bovine lactoferrin inhibited growth of the probiotic strain B. breve M-16V in pasteurised human breast milk. Although unpasteurised human breast milk and human lactoferrin had the greatest antimicrobial activity against all bacterial species tested, higher doses of bovine lactoferrin also showed activity against B. breve and. S. epidermidis. This study suggests that simultaneous administration of lactoferrins and probiotics may affect colonisation with probiotic bacteria, warranting further investigations.

Review concludes that specific recommendations are needed to harmonise the provision of fresh mother's milk to their preterm infants

AIM

There are no specific recommendations for using a mother's fresh milk for her preterm infant. We reviewed the available evidence on its collection, storage and administration.

METHODS

The working group of the French Neonatal Society on fresh human milk use in preterm infants searched the MEDLINE database and Cochrane Library up to June 2017 for papers published in English or French. They specifically analysed 282 papers providing information on prospective, retrospective and clinical studies and examined guidelines from various countries.

RESULTS

The review concluded that fresh mother's own milk should be favoured in accordance with the latest recommendations. However, it must be carried out under stringent conditions so that the expected benefits are not offset by risks related to different practices. The working group has summarised the best conditions for feeding preterm infants with human milk, balancing high nutritional and immunological quality with adequate virological and bacteriological safety. Professionals must provide parents with the necessary conditions to establish breastfeeding, together with specific and strong support.

CONCLUSION

Based on their review, the working group has made specific recommendations for using fresh mother's own milk under careful conditions, so that the expected benefits are not offset by risks related to practices.

Bovine Colostrum for Preterm Infants in the First Days of Life: A Randomized Controlled Pilot Trial

OBJECTIVES

Mother's own milk (MM) is the best nutrition for newborn preterm infants, but is often limited in supply just after birth. Pasteurized human donor milk (DM), and especially preterm infant formula (IF) are less optimal diets than MM. We hypothesized that it is feasible to use bovine colostrum (BC), the first milk from cows, as a supplement to MM, during the first weeks after preterm birth.

METHODS

In an open-label, randomized, controlled pilot safety trial, supplementation of MM with BC was compared with DM supplementation (Danish unit) or IF supplementation (Chinese unit). If MM was limited or lacking, BC, DM or IF were given according to local feeding guidelines during the first 14 days of life.

RESULTS

Forty infants were included and randomized in Denmark and in China, with gestational ages 29.9 ± 0.4 and 31.1 ± 0.2 weeks, respectively. Infants supplemented with BC received more enteral protein (P < 0.05) and tended to reach full enteral feeding earlier (China only). Eight infants fed BC showed a temporary elevation in plasma tyrosine on day 7, versus 2 infants in the DM/IF groups. There were no differences between diet groups in feeding intolerance or clinical adverse events.

CONCLUSIONS

Our results indicate that it is feasible to use BC as a supplement to MM during the first weeks of life to increase enteral protein intake in preterm infants. Plasma tyrosine levels may be a good marker for excessive protein intake. A larger randomized trial is required to test the safety and possible short- and long-term clinical benefits of BC supplementation during the first weeks of life for preterm infants.

Redox properties of transitional milk from mothers of preterm infants

AIM

There is a discrepancy between the amount of transitional milk produced by mothers of preterm infants and the low capacity of premature infants to consume it. This milk can be used in milk banks, but previous studies found that there are large variations in the level of host-defence proteins in individual samples of milk from mothers of premature infants, which implies that large individual variations in antioxidative defence composition are also possible.

METHODS

Milk samples were collected from 20 healthy mothers of preterm infants. We determined the values for non-enzymatic antioxidative capacity parameters (oxygen radical absorbance capacity (ORAC)), static oxidation-reduction potential (ORP), activities of antioxidant defence enzymes and the amount of vitamin C in whole milk, skim and whey fractions of transitional milk.

RESULTS

The main low-molecular-weight antioxidant in transitional milk is vitamin C and most of it is contained in whey. ORAC is higher in whole transitional milk than in skim milk and whey, and ORP is lower in whole transitional milk than that in skim milk and whey. Antioxidative enzyme activities are similar in all individual samples of transitional milk from mothers of preterm infants.

CONCLUSIONS

Our results indicate that transitional milk of mothers of preterm infants shows slow individual variations in antioxidative defence composition; therefore, it can be used in human milk banks.

Bacteriological and Immunological Profiling of Meconium and Fecal Samples from Preterm Infants: A Two-Year Follow-Up Study

An abnormal colonization pattern of the preterm gut may affect immune maturation and exert a long-term influence on the intestinal bacterial composition and host health. However, follow-up studies assessing the evolution of the fecal microbiota of infants that were born preterm are very scarce. In this work, the bacterial compositions of fecal samples, obtained from sixteen 2-year-old infants were evaluated using a phylogenetic microarray; subsequently, the results were compared with those obtained in a previous study from samples of meconium and feces collected from the same infants while they stayed in the neonatal intensive care unit (NICU). In parallel, the concentration of a wide range of cytokines, chemokines, growth factors and immunoglobulins were determined in meconium and fecal samples. Globally, a higher bacterial diversity and a lower interindividual variability were observed in 2-year-olds' feces, when compared to the samples obtained during their first days of life. Hospital-associated fecal bacteria, that were dominant during the NICU stay, seemed to be replaced, two years later, by genera, which are usually predominant in the healthy adult microbiome. The immune profile of the meconium and fecal samples differed, depending on the sampling time, showing different immune maturation statuses of the gut.

"Omics" in Human Colostrum and Mature Milk: Looking to Old Data with New Eyes

Human Milk (HM) is the best source for newborn nutrition until at least six months; it exerts anti-inflammatory and anti-infective functions, promotes immune system formation and supports organ development. Breastfeeding could also protect from obesity, diabetes and cardiovascular disease. Furthermore, human colostrum (HC) presents a peculiar role in newborn support as a protective effect against allergic and chronic diseases, in addition to long-term metabolic benefits. In this review, we discuss the recent literature regarding "omics" technologies and growth factors (GF) in HC and the effects of pasteurization on its composition. Our aim was to provide new evidence in terms of transcriptomics, proteomics, metabolomics, and microbiomics, also in relation to maternal metabolic diseases and/or fetal anomalies and to underline the functions of GF. Since HC results are so precious, particularly for the vulnerable pre-terms category, we also discuss the importance of HM pasteurization to ensure donated HC even to neonates whose mothers are unable to provide. To the best of our knowledge, this is the first review analyzing in detail the molecular pattern, microbiota, bioactive factors, and dynamic profile of HC, finding clinical correlations of such mediators with their possible in vivo effects and with the consequent impact on neonatal outcomes.

Perinatal Microbiomes' Influence on Preterm Birth and Preterms' Health: Influencing Factors and Modulation Strategies

Microbial communities inhabiting the human host play important roles in maintaining health status, including reproduction and early life programming, which is particularly important in the context of preterm neonates' health. Preterm birth (PTB) is often the result of a microbial dysbiosis or infection. In addition, preterm neonates experience different levels of organ immaturity and an abnormal gut microbiota establishment, as compared to full-term neonates. This exacerbates their developmental problems and can have negative consequences at systemic level. In addition, preterm babies are commonly exposed to delayed enteral feeding and hospital environments, which increases the risk of short- and long-term health problems. Some of these clinical conditions, such as necrotizing enterocolitis or sepsis, may be life threatening, whereas others may translate into life-long conditions, including cognitive problems. Increasing scientific interest has focused on understanding developmental problems in preterm neonates related to abnormalities in the settlement of their microbial communities, with the final goal of selecting appropriate microbiome-targeted strategies (eg, probiotics), to reduce preterm health risks and improve overall quality of life.This review aims to summarize current knowledge on microbiological factors influencing PTB initiation and gastrointestinal development, and on the health consequences to the preterm neonate. Scientific evidences on dietary strategies reducing PTB incidence and minimizing sequelae in this particularly sensitive human group subpopulation are also discussed.

Changes in the Immune Components of Preterm Human Milk and Associations With Maternal and Infant Characteristics

OBJECTIVE

To describe difference in cytokines, chemokines, and growth factors (CCGFs) and secretory immunoglobulin A (sIgA) in the breast milk of mothers who gave birth preterm and maternal or infant characteristics related to these immune components.

DESIGN

A prospective, repeated-measures, one-group design.

SETTING

Data were collected at an 82-bed NICU in West Central Florida.

PARTICIPANTS

Seventy-six very-low-birth-weight infants weighing less than 1,500 g and their mothers.

METHODS

Daily aliquots of breast milk from mothers of preterm infants were collected from the daily infants' feedings and pooled at the end of each week, and CCGFs and sIgA were measured weekly with MagPix multiplexing (Luminex, Austin, TX) and enzyme-linked immunosorbent assay.

RESULTS

The CCGFs showed high individual variability, but the levels of most CCGFs and sIgA fell over time. Immune variables were generally greater in milk from mothers of infants smaller than 1,000 g. The breast milk of mothers of male preterm infants had significantly greater sIgA than the breast milk of mothers of female preterm infants. We found relationships between age, body mass index, parity, sIgA, and some of the CCGFs in the breast milk of women who gave birth preterm.

CONCLUSION

Immune molecules declined in concentration over time in the breast milk of mothers who give birth preterm during the NICU stay, and maternal and infant factors appeared to play some role in the levels of these immune molecules. Further exploration of this relationship is warranted.

Antibiotics, pediatric dysbiosis, and disease

Antibiotics are by far the most common medications prescribed for children. Recent epidemiological data suggests an association between early antibiotic use and disease phenotypes in adulthood. Antibiotic use during infancy induces imbalances in gut microbiota, called dysbiosis. The gut microbiome's responses to antibiotics and its potential link to disease development are especially complex to study in the changing infant gut. Here, we synthesize current knowledge linking antibiotics, dysbiosis, and disease and propose a framework for studying antibiotic-related dysbiosis in children. We recommend future studies into the microbiome-mediated effects of antibiotics focused on four types of dysbiosis: loss of keystone taxa, loss of diversity, shifts in metabolic capacity, and blooms of pathogens. Establishment of a large and diverse baseline cohort to define healthy infant microbiome development is essential to advancing diagnosis, interpretation, and eventual treatment of pediatric dysbiosis. This approach will also help provide evidence-based recommendations for antibiotic usage in infancy.

Human milk pasteurization: benefits and risks

PURPOSE OF REVIEW

Recent findings substantiate that the optimal method of nourishing preterm, very low birth weight infants (VLBW, born <1500 g) is through appropriately nutrient-enriched human milk, which is frequently provided as pasteurized donor milk. The availability of donor milk for VLBW infants during initial hospitalization continues to increase with the launch of new milk banks in North America. The majority of North American neonatal ICUs now have written policies governing the provision of donor milk. The purpose of this review is to summarize recent evidence regarding the risks and benefits of pasteurization of human milk and outcomes associated with its provision to VLBW preterm infants.

RECENT FINDINGS

Studies investigating the impact of collection, storage and pasteurization on the bacteriostatic, immunologic and nutritional aspects of human milk continue to be published, generally revealing a partial, but not complete reduction in bioactivity. Risk of contamination of pasteurized donor human milk with pathogenic agents is mitigated through pasteurization. New pasteurization methods aiming to maintain the safety of pooled human milk while better preserving bioactivity are under investigation.

SUMMARY

Provision of a human milk-derived diet to preterm VLBW infants is associated with improved outcomes.