Donation barriers, enablers, patterns and predictors of milk bank donors in the United States and United Kingdom

Pasteurised donor human milk is recommended for very low birthweight infants who do not have access to their mother's milk. Although the use of donor milk continues to increase, little is known about the donation experiences of milk bank donors. We aimed to describe and compare enablers, barriers and patterns of human milk donation and identify factors predicting donation volume in a convenience sample of approved milk bank donors in the United Kingdom and the United States. A cross-sectional online survey was conducted from August 2022 to December 2022. Approved milk bank donors (n = 556) from three milk banks in the United States (n = 369, Mothers' Milk Bank of Florida, Mother's Milk Bank of North Texas and Northwest Mothers Milk Bank) and one milk bank in the United Kingdom (n = 187, Hearts Milk Bank) completed the survey. A substantial portion of donors in both settings reported participating in other forms of milk exchange (51% of U.S. donors vs. 39% of UK donors, p = 0.009). Top donation barriers reported in both settings were completing the serological screening and having enough space to store collected milk. Most donors started donating when their infant was 3 months old or older and reported donating mature milk. The most common source of information related to milk banking in each setting was the internet (United Kingdom-70% vs. United States - 63%, p = 0.112). Variables that predicted lifetime donation volume differed between the United States and the United Kingdom, highlighting the importance of setting-specific milk banking research.

Human Milk Nutrient Composition Data is Critically Lacking in the United States and Canada: Results from a Systematic Scoping Review of 2017-2022

Characterization of the nutrients in human milk is important to understand the dietary and developmental requirements of infants. The objective of this review was to summarize the state-of-the-science on the nutrient composition of human milk in the United States and Canada published from 2017 to 2022. Four databases were searched for randomized controlled studies and others given the scoping nature of this review. We limited type to mature milk collected 21 d postpartum and beyond from lactating individuals in the United States and Canada who gave birth at 37-wk gestation or later (full-term). Outcomes of interest included traditional macro- and micronutrients, including human milk oligosaccharides (HMOs), and milk volume. The publication date range was selected as January 1, 2017, to the day the literature search was performed. A total of 32 articles were included in the scoping review from primarily longitudinal cohort or cross-sectional designs. The most prevalent sample collection method was full-breast expression (n = 20) with most studies (n = 26) collecting samples from a single timepoint. Carbohydrates (HMOs [n = 12], glucose [n = 8], and lactose [n = 6]) and protein (n = 5) were the most frequently assessed nutrients in this body of work, with consensus among studies that glucose is present in limited concentrations compared to lactose (24-64 mg/dL compared with 6-7 g/dL) and that HMOs are influenced by temporality and secretor status. Included studies displayed an overall level of heterogeneity and sparsity paralleling previous reports and nutrient data in the USDA FoodData Central system. Much of the data extracted from retained articles generally provided analysis of a specific nutrient or group of nutrients. Moreover, many studies did not use the preferred analytical methods as outlined by the Human Milk Composition Initiative to increase measurement confidence. Up-to-date nutrient composition data of human milk is still greatly needed as it is paramount for the management of infant feeding, assessment of infant and maternal nutritional and health needs, and as a reference for infant formula development.

Major and trace mineral composition of milk from lactating women following vegan, vegetarian and omnivore diets

Approximately one-in-ten reproductive age adults in the USA follow a plant-based diet, yet there is limited information on the influence of vegan and vegetarian diets on the mineral composition of breast milk. This study explored the major and trace mineral composition in breast milk and associations with maternal diet patterns. We used a cross-sectional design to collect a single sample of breast milk from individuals following vegan (n 23), vegetarian (n 19) and omnivore (n 21) diet patterns. Plant-based diet (n 42) was defined as following either vegan or vegetarian diets. Sixteen minerals were assessed using inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry. Data were evaluated using traditional statistical techniques and five different machine learning approaches. The distribution of Se (median; quartile 1 and 3) was significantly different between groups (vegetarians 21, 18-26 µg/l; vegans 19, 18-25 µg/l and omnivores 17, 14-20 µg/l; P = 0·007) using a Kruskal-Wallis test. Machine learning techniques also identified Se as a potential biomarker for differentiating breast milk by maternal diet pattern. Individuals following a plant-based diet generally had a lower BMI, higher breast milk Se and lower breast milk I and Fe concentrations compared with those following omnivore diets. This suggests that maternal dietary pattern (plant-based v. omnivore) may be helpful clinical information to consider when caring for the breast-feeding dyad, with the strongest evidence related to differences in Se concentration.

The Influence of Oligosaccharides when Measuring Lactose and Total Carbohydrates in Human Milk and Comparison of Methods

BACKGROUND

Understanding how human milk impacts growth requires valid analytical methods for quantifying the composition. Lactose, the most abundant constituent in human milk and a predominant source of energy, is often assessed using methods borrowed from the bovine dairy industry. However, the carbohydrate matrices of bovine and human milk are quite different, especially as they relate to human milk oligosaccharides (HMOs), each with a terminal lactose unit that may influence analytical methods.

OBJECTIVES

Our goals were to determine the extent to which HMOs influence common analytical methods for measuring carbohydrates in human milk and to compare common methods for measuring lactose.

METHODS

Two sets of experiments were performed. In the first set, native and HMO-spiked human milk samples (n = 16 each) were assessed and compared using 4 methods: AOAC 2006.06 (based on the Megazyme enzymatic assay), BioVision enzymatic assay, ultraperformance LC with MS, and infrared analysis. In the second set, human milk samples (n = 20) were assessed using 2 methods approved for measuring lactose in bovine milk: AOAC 984.22 that uses high-performance LC and refractive index detection and AOAC 2006.06 prepared using both volume and weighted dilutions.

RESULTS

Native and HMO-spiked samples were not significantly different in lactose using AOAC 2006.06 and ultraperformance LC with MS but were significantly different using BioVision (mean difference = 0.2 g/dL; 95% CI: 0.1, 0.4; P = 0.005). Total carbohydrate measurements assessed using infrared were also higher after HMO spiking (mean difference = 0.4 g/dL; 95% CI: 0.3, 0.6; P < 0.001). Only AOAC methods 984.22 and 2006.06 for measuring lactose were very highly correlated (r > 0.90, P < 0.001).

CONCLUSIONS

AOAC methods 984.22 and 2006.06 are comparable for measuring lactose in human milk and are not influenced by HMOs. HMOs influence other enzymatic methods as well as infrared analysis, which leads to an overestimate of energy values. J Nutr 2023;x:xx.

COVID-19 Severity Is Associated with Selenium Intake among Young Adults with Low Selenium and Zinc Intake in North Carolina

Background

The effects of coronavirus disease 2019 (COVID-19) remain a global public health emergency because of the ensuing economic burden and death. With robust research into vaccines, antibody treatments, and antiviral drugs for COVID-19, there is still a dearth of evidence on the role of an individual's nutritional status on the severity of COVID-19.

Objective

This study aimed to investigate the association between selenium (Se) and zinc (Zn) status and COVID-19 severity among individuals diagnosed with COVID-19 in North Carolina.

Methods

Subjects (n = 106) were recruited remotely as part of the Nutrition and COVID-19 in North Carolina (NC-NC) study and filled out online screening questionnaires and dietary surveys. Toenail samples from 97 participants were analyzed to determine Se and Zn concentrations. To assess the severity of severe acute respiratory coronavirus (SARS-CoV)-2 infection, subjects were asked about the presence and duration of 10 commonly reported symptoms. These responses were used to calculate a COVID-19 severity index (CSI). The relationship between Se and Zn status (intake and toenail concentrations) and CSI was explored using a regression analysis.

Results

Our results showed that the median (25th, 75th percentiles) dietary Se and Zn intake from selected food sources were 65.2 μg (43.2, 112.9) and 4.3 mg (1.8, 8), respectively. Headache, cough, loss of smell or taste, and fever were reported by at least half of the participants. In stepwise regression analysis, among individuals with low Se and Zn intake (below the median), Se intake was inversely associated with increasing CSI (β = -0.66; 95% CI: -1.21, -0.11; P = 0.02).

Conclusions

Findings from this study support a potential benefit of increasing the intake of dietary Se to mitigate the severity of SARS-CoV-2 infection.

Investigating donor human milk composition globally to develop effective strategies for the nutritional care of preterm infants: Study protocol

BACKGROUND

Globally, almost 15 million infants are born prematurely each year, disproportionately affecting low and middle-income countries. In the absence of mother's milk, the World Health Organization recommends using donor human milk (DHM) due to its protective effect against necrotizing enterocolitis, a life-threatening intestinal disorder. The use of DHM is increasing globally, with many low and middle-income countries integrating donor milk banks into their public health strategies to reduce neonatal mortality, yet very little is known about the nutritional composition of DHM. Additional knowledge gaps include how DHM composition is influenced by milk banking practices, and whether preterm nutrient recommendations are achieved when DHM is used with commercially available fortifiers.

METHODS

We designed a multi-site study with eight geographically diverse milk bank partners in high, middle, and low-income settings that will examine and compare a broad range of nutrients and bioactive factors in human milk from 600 approved milk bank donors around the world to create comprehensive, geographically diverse nutrient profiles for DHM. We will then simulate the random pooling of 2 to 10 donors to evaluate the impact of pooling as a potential strategy for milk banks to manage nutrient variability in DHM. Finally, we will evaluate whether commercially available fortifiers meet nutrient recommendations when used with DHM.

DISCUSSION

We expect that results from this study will improve nutritional care globally for the growing number of preterm infants who receive donor human milk.

Prevalence and Predictors of Low Breast Milk Iodine Concentration in Women Following Vegan, Vegetarian, and Omnivore Diets

Purpose: Breast milk iodine concentration (BMIC) from vegan and vegetarian lactating mothers has not previously been evaluated. The goal of this study was to assess BMIC from vegans, vegetarians, and omnivores and to assess intake of iodine by breastfed infants. Materials and Methods: Breast milk samples from vegans (n = 12), vegetarians (n = 6), and omnivores (n = 12) living in the United States were analyzed. BMIC was determined at the mass-to-charge ratio (m/z) 127 by inductively coupled plasma mass spectrometry (ICP-MS) using an Agilent 8800 ICP-MS/MS (Agilent Technologies). Results: There was a significant difference in mean BMIC between participants following a plant-based diet (vegan and vegetarian, n = 18) compared with omnivores [4.42 versus 5.02 Ln(BMIC), respectively; p = 0.0405]. In linear regression to predict BMIC, vegan diet was a negative predictor (standardized β = -0.409) and use of multi- or prenatal supplements was a positive predictor (standardized β = 0.319). There were differences in the percentage of inadequate BMIC per maternal diet (75% vegan, 67% vegetarian, omnivore 58%) but this did not reach statistical significance. In 67% of the samples (20/30) BMIC was lower than the National Academy of Medicine's adequate intake (AI), assuming infant milk consumption of 0.78 L/day. Conclusions: Most samples from vegans and vegetarians contained a lower BMIC than AI for infants 0-6 months. Counseling of pregnant vegans and vegetarians should highlight importance of iodine supplementation during lactation. The findings are based on a small number of samples, especially for vegetarians, and thus, they need to be confirmed by larger studies.

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.

A Cross-Sectional Assessment of Human Milk Oligosaccharide Composition of Vegan, Vegetarian, and Nonvegetarian Mothers

Purpose: Recently, maternal nutrient intake has been associated with human milk oligosaccharides (HMOs) composition. The goal of this study was to assess HMO composition in breast milk samples from vegan, vegetarian, and nonvegetarian lactating women. Second, we assessed impact of maternal body mass index (BMI), age, parity, and lactation stage on HMO composition. Materials and Methods: A cross-sectional analysis of HMO composition from vegan (n = 26), vegetarian (n = 22), and nonvegetarian (n = 26) lactating women was carried out. The majority of participants took dietary supplements. Results: In an unadjusted bivariate model, there was no difference in individual HMO composition, total HMO-bound fucose and HMO-bound sialic acid, or diversity and evenness scores by diet group. When adjusting for factors that significantly differed between groups (maternal BMI and lactation stage), no differences in HMO composition were observed. Secretor status was significant for 13 of the outcome variables with the strongest positive relationship with total HMO (β = 0.922) and HMO-bound fucose (β = 0.910), and the strongest negative relationship with sialyl-lacto-N-tetraose b (LSTb) (β = -0.544). Lactation stage was significant for eight analytes, with the strongest positive impact on 3'sialyllactose (3'SL) (β = 0.433), and the strongest negative impact on 6'sialyllactose (6'SL) (β = -0.519). Maternal BMI had a significant positive relationship with total HMO composition (β = 0.113) and 3'SL (β = 0.325). Conclusions: Lactating women who consume plant-based diets do not produce different breast milk as it relates to HMO composition.

Nondiet Weight-Neutral Curricula Limited in Current Accredited US Dietetic Programs

OBJECTIVE

Determine awareness and prevalence of, and interest in nondiet weight-neutral (NDWN) focused curriculum and factors associated with the presence in accredited dietetic programs throughout the US.

METHODS

Online cross-sectional survey sent to directors of US Coordinated Programs (n = 60) and Didactic Programs in Dietetics (n = 214).

RESULTS

116 programs (42%) responded, 95% reported knowledge of NDWN approaches to weight management like Health at Every Size. Most schools (72%) included NDWN in their curriculum, mostly in a single lecture (53%). Most respondents (74%) reported interest in an NDWN curriculum. Common factors for not including NDWN were: lack of trained and knowledgeable staff (35%) and insufficient space in the curriculum to incorporate additional topics (35%).

CONCLUSIONS AND IMPLICATIONS

Most knew of NDWN approaches and included in curricula but only as 1 lecture. Faculty training and curriculum flexibility may help support the increased incorporation of NDWN approaches.

Methods of mixing donor human milk during bottling results in fat differences between samples within a pool

The influence of milk-banking processes on nutrients in donor human milk (DHM) is largely unknown. Previous studies have measured nutrients between pools of DHM, but within-pool nutrient differences (between bottles from the same pool) have yet to be elucidated. The objective of this study was to gain a better understanding of the effect of different mixing characteristics on the distribution of fat, protein, IgA, and lysozyme in bottled, raw DHM. Pools of DHM were created in a laboratory setting according to published human milk-banking guidelines and assigned to a mixing treatment (mixing during bottling method, pooling container material, and refrigerated hold time). Four mixing protocols using glass pooling containers and a 1-h refrigerated hold time were tested: control (no mixing during bottling); manual-A (Man-A, hand swirl after pouring 3 bottles); manual-B (Man-B, hand swirl after pouring every bottle); and mechanical-G (Mech-G, continuous stirring with a magnet). As secondary objectives, we compared the effect of a glass and a plastic pooling container with mechanical mixing (mechanical-P, Mech-P), and compared refrigerated delays of 1 and 24 h before bottling with manual mixing (manual-A24, Man-A24). To control for differences in nutrient content, comparisons between treatments were made using absolute percent difference from the treatment-specific mean; and comparisons within a treatment were made using the ratio of fat content in a bottle to fat content in the first bottle of the same pool. We did not observe differences in nutrient distribution between Man-A, Man-B, and Mech-G in pools held for 1 h, but all were significantly different from the control for fat. There were no differences between glass or plastic pooling containers when mechanical mixing was used. Holding a pool in the refrigerator for 24 h before bottling created significantly greater fat distribution than holding a pool for 1 h. Outcomes were the result of controlled experiments. In summary, manual and mechanical mixing of 1,700-mL DHM pools produces similar fat and protein distributions when DHM is pooled and bottled after a 1-h hold time. When DHM is held for 24 h before bottling, more research is needed to determine the duration of initial mixing needed to reduce fat variability between bottles.

Method for Removing Thawed Human Milk From a Plastic Storage Bag Impacts Fat Retention

OBJECTIVES

Determine how thaw stage and bag manipulation (folding and squeezing) influence the retention of fat and number of aerobic bacteria colony-forming units when decanting human milk (HM) from plastic storage bags.

METHODS

Lactating women (n = 40) in the Greensboro, North Carolina area were recruited to provide fresh HM. Samples were equally divided and frozen in storage bags for 2 months. Two thaw stages (ice/liquid) and the use of bag manipulation (yes/no) were assessed. Fat was measured using ether extraction and bacteria were measured using plate enumeration. Paired t tests were used to compare the effects of thaw stage and bag manipulation on post-thaw fat content. Repeated measures analysis of variance was used to compare the effect of bag manipulation on pre- and post-thaw bacteria.

RESULTS

Fat retention was not significantly different when thawing to liquid versus ice (mean difference = 0.10 g/dL; n = 17 paired samples; P = 0.07). Decanting with bag manipulation retained more fat than decanting without manipulation, but only when HM was thawed to liquid (mean difference = 0.13 g/dL; n = 11 paired samples; P = 0.005), not when HM was thawed to ice (P = 0.47). Bag manipulation did not increase total aerobic bacteria for either thaw stage (P = 0.49).

CONCLUSIONS

Fat retention is influenced by the method of removing previously frozen HM from plastic storage bags. Folding and squeezing the storage bag when decanting HM thawed to a liquid state increases fat recovery without increasing bacterial contamination.

Donor Human Milk Use in Populations Other than the Preterm Infant: A Systematic Scoping Review

Introduction: Exclusive breastfeeding is recommended for an infant's first 6 months of life. If unable to breastfeed, expressed breast milk, including donor human milk (DHM), is recommended for optimal nutrition. Benefits of DHM in preterm infants have been established by extensive research. However, less is known about DHM use in other populations. Objective: To conduct a scoping review of the literature regarding DHM use in populations other than preterm infants. Materials and Methods: PubMed and Clinicaltrials.gov were used to search for articles and clinical trials published between January 1, 2000 and February 29, 2020. In total, 182 articles and reports were identified and screened by 2 independent reviewers. Results: Twenty-six articles met inclusion criteria and were reviewed. Studies were mostly observational in design and included infants born >35 weeks gestational age with health risks (9/26) and healthy infants (14/26). Most studies in infants with health risks (7/9) investigated clinical outcomes, with small, observational studies suggesting potential improvements in feeding tolerance and gastrointestinal health. Regarding healthy infants, no studies addressed growth, only one study measured clinical outcomes, and findings related to breastfeeding outcomes were conflicting. Over half of the studies reviewed (15/26) were not designed to establish a potential relationship between DHM use and relevant health-related outcomes. Conclusion: The current evidence of DHM use in populations other than preterm infants is limited by lack of direct health measures and infrequent use of randomized trials. More research is warranted to investigate clinical, growth, and breastfeeding outcomes.

National Prevalence of Donor Milk Use Among Level 1 Nurseries

BACKGROUND AND OBJECTIVES

Donor milk use has increased among very preterm infants because of mounting evidence of health benefits; however, the extent that donor milk is used among healthy term infants in level 1 nurseries is unclear. We aimed to determine (1) national prevalence of and (2) hospital factors associated with donor milk use in level 1 nurseries.

METHODS

Among 3040 US birthing hospitals, we randomly selected hospitals from each of 4 US regions (119 in northeast, 120 in Midwest, 116 in west, and 103 in south) for a total of 458 hospitals. We surveyed the nursing leaders of these hospitals from October to December 2017 regarding routine use of donor milk in the level 1 nursery (yes or no). To estimate national prevalence, we weighted responses according to the number of birthing hospitals within each region. We examined relationships between routine donor milk use in the level 1 nursery and hospital characteristics using multivariable logistic regression.

RESULTS

In total, 214 of 458 (47%) nursing leaders responded. The national prevalence of routine donor milk use in level 1 nurseries was 17.6%. Eighty-five percent of donor milk programs were ≤5 years old. Donor milk use occurred more often in hospitals with ≥1500 annual births (41.7%), compared to ≤500 annual births (6.3%) (adjusted odds ratio 7.8; 95% confidence interval 1.8-34.4), and in the west (30.9%), compared to the northeast (10.5%) (adjusted odds ratio 4.1; 95% confidence interval [1.1-14.9]).

CONCLUSIONS

Although there is limited evidence to support donor milk for healthy infants in the nursery, nearly one-fifth of level 1 US nurseries routinely used donor milk in 2017.

The Nutritional Composition and Energy Content of Donor Human Milk: A Systematic Review

The American Academy of Pediatrics recommends donor human milk (DHM) as the preferred feeding strategy for preterm infants when the milk of the mother is unavailable, based on conclusive evidence of lower rates of necrotizing enterocolitis with DHM feedings compared with preterm infant formula. The nutritional composition of DHM may differ from maternal milk for many reasons including differences in maternal characteristics, milk collection methods, and the impact of donor milk banking practices. The purpose of this systematic review is to examine the literature regarding research on the fat, protein, carbohydrate, vitamin, and mineral composition of DHM obtained through nonprofit milk banks or commercial entities. PubMed, CINAHL, and Scopus databases were searched for articles published between 1985 and 30 April, 2019. In total, 164 abstracts were screened independently by 2 investigators, and 14 studies met all inclusion criteria. Studies were predominantly small (<50 samples) and measured macronutrients. Few studies assessed vitamins and minerals. Information bias was prevalent due to the use of a variety of analytical methods which influence accuracy and cross-study comparisons. Other sources of information bias included missing information regarding methods for protein and calorie assessment. Despite these limitations, existing research suggests the potential for 2-fold and greater differences in the fat, protein, and energy composition of DHM, with mean values for energy and fat often below clinical reference values expected for human milk. Further research is warranted regarding the nutritional composition of DHM, with a prioritization on measuring macronutrients and micronutrients using established reference methods.

Fat and Protein Variability in Donor Human Milk and Associations with Milk Banking Processes

Background: The impact of milk banking processes on macronutrient variability in donor human milk (DHM) is largely unknown. Objective: To gain a better understanding of fat and protein composition in DHM and assess potential relationships with modifiable milk bank processes. Methods: Samples of raw, pooled DHM were collected from 20 milk banks (n = 300) along with the following processing attributes: if macronutrient analysis was used to select donors for pooling (target pooling; yes/no), number of donors per pool, pooling container material (glass/plastic/other), and method for mixing during bottling (manual/mechanical). Fat and protein were assessed. Homoscedasticity was assessed and magnitude of the spread was quantified. Results: Fat ranged from 1.9 to 6.1 g/dL (n = 298) and protein ranged from 0.7 to 1.4 g/dL (n = 300). Variability in fat was significantly lower in samples that had been target pooled (p = 0.04), contained more donors per pool (p < 0.001), and had been mixed mechanically (p < 0.001). Variability in protein was significantly lower in samples that contained more donors per pool (p = 0.001). In a stratified analysis, increasing the number of donors per pool only reduced nutrient variability in samples that were not target pooled. Conclusion: For milk banks that do not target pool, using a greater number of donors in a pool may reduce fat and protein variability.

Total Water-Soluble Choline Concentration Does Not Differ in Milk from Vegan, Vegetarian, and Nonvegetarian Lactating Women

BACKGROUND

Choline is an essential nutrient for brain growth and other processes in the developing neonate. The impact of a maternal plant-based diet on the choline composition of breast milk is unknown.

OBJECTIVE

We assessed the water-soluble choline content of milk from lactating women in the United States following 3 dietary patterns: vegan, vegetarian, and nonvegetarian.

METHODS

We conducted a cross-sectional study of 74 healthy lactating women who provided a single breast-milk sample using a standardized collection protocol. Participants completed a food-frequency screener and were classified as follows: nonvegetarians (NONVEG) consumed meat; vegetarians (VEGT) consumed milk, dairy, and/or fish; and vegans (VEGAN) consumed animal products less than monthly. Primary outcomes measured were the concentration (in milligrams per liter) and distribution (percentage) of choline from the following water-soluble forms: free choline, phosphocholine (PCho), and glycerophosphocholine (GPC). Differences between diet groups were evaluated with ANOVA.

RESULTS

There was a wide range in breast-milk total water-soluble choline (4-301 mg/L), with no significant difference (P > 0.05) by maternal diet pattern. There were differences in choline forms, with VEGAN having a greater mean ± SD concentration and distribution of choline derived from GPC (62.7 ± 25.3 mg/L) than VEGT (47.7 ± 21.2 mg/L) and NONVEG (42.4 ± 14.9 mg/L) (P = 0.0052). There was a lower mean ± SD percentage of choline from PCho (P = 0.0106) in VEGAN (32.5% ± 18.3%) than in VEGT (46.1% ± 18.3%) and NONVEG (44.8% ± 15.7%). Lactation stage and maternal BMI were significantly associated with some choline forms.

CONCLUSIONS

There was a wide range of water-soluble choline concentrations in the milk of healthy lactating women following vegan, vegetarian, and nonvegetarian diets, with no observed difference in total water-soluble choline concentration by maternal diet. This suggests that maternal plant-based diet by itself is not a risk factor for low breast-milk choline.

Accuracy and Reliability of Infrared Analyzers for Measuring Human Milk Macronutrients in a Milk Bank Setting

BACKGROUND

Infrared (IR) analysis is an emerging technology that may be a useful tool for milk banks to manage the nutrient variability in donor human milk.

OBJECTIVE

To evaluate the accuracy, reliability, and comparability of commercial infrared analyzers for measuring human milk macronutrients in a milk bank setting.

METHODS

Three nonprofit milk banks received blinded test kits of human milk that had been assessed using reference methods. Four infrared instruments were used to measure macronutrients as follows: 1 filtered mid-IR, 2 Fourier-transformed full-spectra mid-IR, and 1 near-IR. Twenty-five unique samples were read concurrently for the accuracy arm. An identical sample was read daily for 1 mo for the reliability arm.

RESULTS

Values for R 2 describing relationships with reference methods for total fat, crude protein, and lactose, were as follows: filtered mid-IR, 0.98, 0.94, and 0.48; Fourier-transformed full-spectra mid-IR, 0.97, 0.93, and 0.36 for instrument 1 and 0.98, 0.98, and 0.31 for instrument 2; and near-IR 0.93, 0.93, and 0.12. There was no significant difference between instruments for crude protein and total fat measurements. There were significant differences in carbohydrate measurements between instruments. For 1 mo of daily measurements in the reliability arm, CVs for filtered mid-IR were ≤4.6%, for Fourier-transformed full spectra mid-IR were ≤1.7%, and for near-IR were ≤5.1%.

CONCLUSIONS

Infrared analysis is an accurate and reliable method for measuring crude protein and total fat in a milk bank setting. Carbohydrate measurements are less accurate and are significantly different between instruments, which will likely lead to differences in derived calorie values.

A cross-sectional study of fatty acids and brain-derived neurotrophic factor (BDNF) in human milk from lactating women following vegan, vegetarian, and omnivore diets

PURPOSE

Essential fatty acids are critical for brain growth and neurodevelopment in infancy. Maternal diet and supplement use have a significant impact on the fat composition of human milk. The objective of this study is to assess supplement utilization patterns and fatty acid and brain-derived neurotrophic factor (BDNF) concentrations in the breast milk of women following vegan, vegetarian, and omnivore diet patterns.

METHODS

This is a cross-sectional, observational study of 74 lactating women in the United States following a vegan (n = 26), vegetarian (n = 22), or omnivore (n = 26) diet pattern. A single breast milk sample was collected from each participant and assessed for fatty acids and BDNF.

RESULTS

Median unsaturated fatty acids in the breast milk of vegan, vegetarian, and omnivores, as a percentage of total fatty acids, was 66.0, 57.8, and 56.2%, respectively (p < 0.001). Total omega-3 percentages were 2.29% for vegans, 1.55% for vegetarians, and 1.46% for omnivores (p < 0.001). Docosahexaenoic acid percentages were not different by diet pattern, but over 80% of participants had milk concentrations below 0.30% of total fatty acids. Reports of omega-3 supplements use (10/74) and weekly seafood consumption (3/74) were limited. BDNF was not detectable in any samples.

CONCLUSIONS

Breast milk from vegans had significantly higher unsaturated fat and total omega-3 fats, and lower saturated fats, trans fats, and omega-6 to omega-3 ratios than their vegetarian and omnivore counterparts. Docosahexaenoic acid concentrations in breast milk were low regardless of maternal diet pattern, and were reflective of low seafood intake and supplement use.

A pilot study on nutrients, antimicrobial proteins, and bacteria in commerce-free models for exchanging expressed human milk in the USA

Expressed human milk can be donated or sold through a variety of channels, including human milk banks, corporations or individuals, or peer-to-peer milk sharing. There is a paucity of research regarding the nutrient and bioactive profiles of expressed human milk exchanged through commerce-free scenarios, including peer-to-peer milk sharing. The study objective was to evaluate the macronutrient, antimicrobial protein, and bacteria composition in expressed human milk acquired via commerce-free arrangements. Expressed human milk samples were collected from the following commerce-free scenarios: milk expressed for a mother's or parent's own infant (MOM; N = 30); unpasteurized milk donated to a non-profit milk bank (BANKED; N = 30); milk expressed for peer-to-peer milk sharing (SHARED; N = 31); and health professional-facilitated milk sharing where donors are serologically screened and milk is dispensed raw (SCREENED; N = 30). Analyses were conducted for total protein, lactose, percent fat and water, lysozyme activity, immunoglobulin A (IgA) activity, total aerobic bacteria, coliform, and Staphylococcus aureus. No bacterial growth was observed in 52/121 samples, and 15/121 had growth greater than 5.0 log colony-forming units/mL. There was no evidence of differences by groups (p > .05) in lactose, fat, water, lysozyme activity, sIgA activity, aerobic bacteria, coliforms, and S. aureus. Mean protein values (95% confidence interval) were 1.5 g/dL (1.4, 1.6) for BANKED, 1.4 g/dL (1.3, 1.5) for MOM, 1.6 g/dL (1.5, 1.7) for SCREENED, and 1.5 g/dL (1.4, 1.6) for SHARED, which was not significantly different (p = .081). This research contributes to growing literature on the risks and benefits of uncompensated, peer-to-peer milk sharing.

Current Trends in Research on Human Milk Exchange for Infant Feeding

Breastfeeding is critical for the healthy growth and development of infants. A diverse range of infant-feeding methods are used around the world today. Many methods involve feeding infants with expressed human milk obtained through human milk exchange. Human milk exchange includes human milk banking, human milk sharing, and markets in which human milk may be purchased or sold by individuals or commercial entities. In this review, we examine peer-reviewed scholarly literature pertaining to human milk exchange in the social sciences and basic human milk sciences. We also examine current position and policy statements for human milk sharing. Our review highlights areas in need of future research. This review is a valuable resource for healthcare professionals and others who provide evidence-based care to families about infant feeding.

Macronutrient variability in human milk from donors to a milk bank: Implications for feeding preterm infants

Background and objective

The composition of human milk varies widely and impacts the ability to meet nutrient requirements for preterm infants. The purpose of this study is to use a large dataset of milk composition from donors to a milk bank to: (1) describe the macronutrient variability in human milk and how it contributes to the ability to meet the protein and calorie targets for the preterm infant using fortification with commercially available multi-nutrient fortifiers; (2) assess how temporal versus subject effects explain macronutrient variability; (3) determine how macronutrient variability contributes to the nutrient distribution in pooled donor milk.

Methods

This is a retrospective, observational study that analyzes the macronutrient data of 1,119 human milk samples from 443 individual donors to a milk bank. We test fortification strategies with potential basic, intermediate, and high protein and calorie commercial fortifiers. Additionally, we simulate the random pooling of multiple donors to model the impact of macronutrient variability on pooled donor milk.

Results

Fat was the most variable nutrient and accounted for 80% of the difference in calories. A subject-effect predicted more of the variability after 4 weeks postpartum in all macronutrients (R² > = 0.50) than a time-effect (R² < = 0.28). When pooling multiple donors, variability was reduced by increasing the number of donors randomly selected for a pool or targeted pooling based on macronutrient analysis of donor pools. Over 75% of mature milk samples fortified with a basic protein fortifier did not meet daily protein targets of 3.5 g/kg without exceeding volumes of 160 ml/kg/day.

Conclusion

There is a strong individual signature to human milk that impacts the pooling of donor milk, and the ability to meet protein and energy requirements for the preterm infant with basic and intermediate protein and calorie fortifiers.

Effects of Refrigerated and Frozen Storage on Holder-Pasteurized Donor Human Milk: A Systematic Review

BACKGROUND

Pasteurized donor human milk (PDHM) is the recommended feeding alternative for preterm infants when mother's own milk is not available. Use of PDHM in United States neonatal hospitals is increasing, although guidelines for the refrigerated and frozen storage are limited.

OBJECTIVE

We aimed to review the current evidence for the storage of Holder PDHM (HPDHM) under refrigerated and frozen storage conditions.

METHODS

A systematic review of the literature was conducted for studies published between 1985 and May 2018. Studies were included if they studied the storage of Holder-pasteurized human milk under refrigerated or frozen storage conditions.

RESULTS

Fourteen studies met the inclusion criteria. Five studies addressed refrigerated storage and nine studies addressed frozen storage. There was little overlap in the outcomes measured or the analytical methods employed. There was concordance in three studies reporting no microbial growth over 4-9 days of refrigerated storage, and in five studies reporting a reduction in fat during 1-8 months of frozen storage. Only one study assessed the storage of HPDHM that had been fortified.

CONCLUSIONS

Long-term refrigerated and frozen storage of HPDHM affects some components in milk more than others. While there is evidence of microbial purity during four or more days of refrigerated storage in clinical conditions, there is limited research on the impact of macro and micronutrients, or the impact of fortifiers. More research is needed in these areas.

Storage of Unfed and Leftover Mothers' Own Milk

OBJECTIVE

The objective was to examine the bacteriological and immunological properties of freshly expressed, previously frozen, and leftover mothers' own milk during storage.

MATERIALS AND METHODS

In the first of two pilot studies, 12 mother-infant dyads participated. The milk studied included freshly expressed unfed and freshly expressed leftover milk. Milk samples were stored at 24°C, 4°C, or -20°C. In the second pilot study, 11 mother-infant dyads participated. The milk studied included milk that had been previously frozen, including previously frozen leftover milk. Milk samples were stored at 24°C and 4°C. After storage in both studies, the milk was analyzed for bacteriological and immunological properties.

RESULTS

Bacteriological and immunological characteristics of freshly expressed unfed and freshly expressed leftover milk and previously frozen unfed and previously frozen leftover milk remained stable during storage at 4°C for at least 6 days. The quality of all groups of mothers' milk declined when stored at 24°C for longer than 3 hours.

CONCLUSIONS

While this study provides evidence that human milk might be safe at longer storage times, storage guidelines should not be revised until more research is performed. This study serves as a call to action for more research on the topic of human milk storage, specifically leftover human milk. The study provides information to inform future study designs on the topic of unpasteurized human milk storage. More research is needed regarding leftover human milk storage with a greater number of participants, determination of the quality of human milk, and the storage of human milk in a real-life setting.

Bacteria and Bioactivity in Holder Pasteurized and Shelf-Stable Human Milk Products

Background: Historically, Holder pasteurization has been used to pasteurize donor human milk available in a hospital setting. There is extensive research that provides an overview of the impact of Holder pasteurization on bioactive components of human milk. A shelf-stable (SS) human milk product, created using retort processing, recently became available; however, to our knowledge, little has been published about the effect of retort processing on human milk. Objective: We aimed to assess the ability of retort processing to eliminate bacteria and to quantify the difference in lysozyme and secretory immunoglobulin A (sIgA) activity between Holder pasteurized (HP) and SS human milk. Methods: Milk samples from 60 mothers were pooled. From this pool, 36 samples were taken: 12 samples were kept raw, 12 samples were HP, and 12 samples were retort processed to create an SS product. All samples were analyzed for total aerobic bacteria, coliform bacteria, Bacillus cereus, sIgA activity, and lysozyme activity. Raw samples served as the control. Results: One raw sample and 3 HP samples contained B. cereus at the time of culture. There were no detectable bacteria in SS samples at the time of culture. Raw samples had significantly greater lysozyme and sIgA activity than HP and SS samples (P < 0.0001). HP samples retained significantly more lysozyme and sIgA activity (54% and 87%, respectively) than SS samples (0% and 11%, respectively). Conclusions: Human milk processed using Holder pasteurization should continue to be screened for the presence of B. cereus. Clinicians should be aware of the differences in the retention of lysozyme and sIgA activity in HP and SS products when making feeding decisions for medically fragile or immunocompromised infants to ensure that patients are receiving the maximum immune protection.

Storage of Unfed and Leftover Pasteurized Human Milk

OBJECTIVE

To determine the impact of storage on bacterial growth and immunological activity of pasteurized human milk and leftover pasteurized human milk that has been exposed to the microflora in an infant's mouth.

MATERIALS AND METHODS

Eighteen mother-infant dyads participated in two separate studies. Mother's milk was pasteurized, and each baby was fed 1 to 2 ounces. Pasteurized and leftover pasteurized milk were stored at room (24°C) and refrigerated temperatures (4°C). After storage, milk was analyzed for bacteria, total protein, lysozyme activity, and secretory immunoglobulin A (SIgA) activity.

RESULTS

In pasteurized and leftover pasteurized milk stored in the refrigerator for 7 days, total aerobic bacteria do not increase significantly and total protein and bioactive proteins are stable. At room temperature, there is a significant increase in total aerobic bacteria in leftover pasteurized milk during 12 hours of storage (p < 0.01) and a significant decrease in total protein and SIgA activity in pasteurized milk during 12 hours of storage (p = 0.02 and p = 0.03, respectively).

CONCLUSIONS

When stored in the refrigerator, pasteurized and leftover pasteurized milk may be stored for at least 7 days when considering the variables studied. Caution should be used when storing pasteurized and leftover pasteurized milk at room temperature to prevent an increase in bacterial growth and a decrease in total protein and SIgA activity.

A longitudinal study of human milk composition in the second year postpartum: implications for human milk banking

While the composition of human milk has been studied extensively in the first year of lactation, there is a paucity of data regarding human milk composition beyond one year postpartum. Policies vary at milk banks around the world regarding how long lactating women are eligible to donate their milk. The primary purpose of this study is to describe longitudinal changes in human milk composition in the second year postpartum to support the development of evidence based guidelines regarding how long lactating women can donate human milk to a milk bank. Nineteen lactating women in North Carolina provided monthly milk samples from 11 months to 17 months postpartum (N = 131), and two non-profit milk banks provided (N = 33) pooled, unpasteurized milk samples from 51 approved donors less than one year postpartum. There was a significant increase (P < 0.05) in the concentration of total protein, lactoferrin, lysozyme, Immunoglobulin A, oligosaccharides and sodium in longitudinal samples of mother's milk between 11 and 17 months postpartum, while zinc and calcium concentrations declined, and no changes were observed in lactose, fat, iron and potassium. Human milk in the second year postpartum contained significantly higher concentrations of total protein, lactoferrin, lysozyme and Immunoglobulin A, than milk bank samples, and significantly lower concentrations of zinc, calcium, iron and oligosaccharides. Accepting milk bank donations beyond one year postpartum is a potential strategy for increasing the supply of donor milk, but may require mineral fortification.