Passively administered fluoxetine reaches the juvenile brain of FSL rats and reduces antioxidant defences, without altering serotonin turnover.

BACKGROUND: Fluoxetine is present in breast milk, yet it is unclear to what extent it, or its active metabolite, norfluoxetine, reaches the brain of the infant and what the effects of such exposure on neurobiological processes are. We therefore aimed to quantify the concentration of passively administered fluoxetine and norfluoxetine in the whole brains of exposed Flinders sensitive line (FSL) offspring and establish their influence on serotonergic function and redox status. METHODS: Adult FSL dams received fluoxetine (10 mg/kg/day), or placebo for fourteen days, beginning on postpartum day 04. Offspring were passively exposed to fluoxetine until postnatal day 18 and euthanized on postnatal day 22. Whole brain fluoxetine, norfluoxetine, serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), and reduced (GSH) and oxidized glutathione (GSSG) concentrations were measured via liquid chromatography-mass spectrometry (LC-MS) analysis. RESULTS: Whole-brain serotonin and 5-hydroxyindoleacetic acid concentrations, and serotonin turnover (5-HIAA/5-HT) were comparable between strains. Treatment-naïve FSL rats had lower GSH and higher GSSG whole-brain concentrations, relative to FRL controls, and an overall decreased GSH/GSSG ratio. Passively administered fluoxetine resulted in undetectable whole-brain concentrations, while norfluoxetine averaged 41.28 ± 6.47 ng/g. Serotonin turnover of FSL rats was unaffected by passively administered fluoxetine, while redox status (GSH/GSSG) was decreased. CONCLUSION: Our findings confirm that passively administered fluoxetine reaches the infant brain in the form of norfluoxetine and may manipulate processes of oxidative stress regulation. Further studies into the long-term bio-behavioural effects are however needed to effectively inform breast feeding mothers on the safety of antidepressant-use.

Maternal Overweight and Obesity and Their Effect on the Growth of the Newborn During the First Six Months of Life.

INTRODUCTION:  Maternal overweight and obesity during pregnancy have been shown to have multiple negative effects on the mother's health, which can even affect the infant's growth by increasing weight gain and altering various indicators, such as weight for age, length for age and weight for length. While breast milk on the other hand reduces these risks, and it's the best and most complete food for the newborn. It's a dynamic fluid capable of being modified to meet the needs of each stage of the newborn, but despite this capacity and the fact that maternal body mass index can have an impact on its components, through complex biological mechanisms, it manages to reduce the negative effects accumulated during pregnancy and even promotes a healthy state in the baby. In a country like Mexico, where overweight and obesity affect a large part of the population, it is important to study their causes and which could be the effect of this increased maternal overweight during pregnancy and lactation on newborns. OBJECTIVE: Identify the alterations associated with increased maternal body mass index during pregnancy and breastfeeding on mothers' health and their possible effect on the growth of the newborn during the first six months of life. MATERIAL AND METHODS: This was a prospective cohort study. Forty-two healthy binomials (mother and child), without problems during delivery and without serious illnesses during the breastfeeding period, were included. Maternal body mass index at the beginning of pregnancy allowed us to create two comparison groups between mothers: one with adequate weight, another with overweight or obesity. Follow-up was carried out once a month during the first six months of life, evaluating the somatometric development of mothers and children. All mothers completed the six-month period of exclusive breastfeeding. RESULTS:  There were differences between both groups of women. The one that included overweight and obese women compared to the group of women with adequate weight had a higher number of pregnancies, abortions, plasma glucose levels in the third trimester of pregnancy, and a lower number of prenatal control visits and plasma platelet levels (all with p<0.05). Regarding the baby's growth, there was a difference between the weight for length classification at 60-, 120-, 150- and 180-day follow-ups. The group to which the mother was assigned with respect to her body mass index at the beginning of pregnancy (adequate weight group and overweight/obese group) was the only factor associated with the risk of the baby being overweight according to weight for length indicator at the 180-day follow-up, with an OR = 5.2 (95%CI 1.02-26.59). CONCLUSIONS: Maternal overweight and obesity during pregnancy have a negative effect on the mother's health and baby's weight gain in its weight-for-length classification during the first six months of life. Although breastfeeding has been shown to have a positive effect on the growth of the baby, exposure to a higher maternal body mass index during pregnancy triggers important metabolic alterations that promote the development of diseases. It is important to establish weight control guidelines in women who wish to become pregnant to reduce the negative effects on the mother and offspring.

Somatic cell count as an indicator of subclinical mastitis and increased inflammatory response in asymptomatic lactating women.

Subclinical mastitis is an asymptomatic inflammatory condition that can be difficult to define and diagnose. In the dairy industry, subclinical mastitis is diagnosed by milk somatic cell counts (SCCs) of ≥250,000 cells mL-1. In this pilot study, we assessed the efficacy of this index to identify human subclinical mastitis by comparing SCC levels with the inflammatory response [interleukin-8 (IL-8) levels] in 37 samples from asymptomatic and 10 clinical mastitis (CM) lactating women. The milk microbiota was determined by 16S rRNA gene sequencing. The SCC of CM samples ranged from 310,000 to 6,600,000 cells mL-1. However, 14 of 37 (37.8%) asymptomatic samples had high SCC (250,000-460,000 cells mL-1), indicating subclinical mastitis. SCC levels significantly (P < 0.001) and positively correlated with milk IL-8 levels reflecting the escalating inflammatory response across subclinical and clinical mastitis samples. Samples with an SCC of ≥250,000 cells mL-1 showed significant increases in IL-8 responses when compared with milk samples from healthy women. The milk microbiome of CM samples was dominated by streptococcal and staphylococcal species (89.9% combined median relative abundance). In contrast, the combined median streptococcal/staphylococcal relative levels were 75.4% and 66.3% in milks from asymptomatic (subclinical mastitis) and healthy groups, respectively. The Streptococcus genus was increased in samples with an SCC of ≥250,000, although this should be interpreted with caution. Thus, the index of ≥250,000 somatic cells mL-1 could be a reliable indicator of subclinical mastitis in humans and should aid future studies investigating the impact of subclinical mastitis on maternal health, breastfeeding behaviors, infant health, and development. IMPORTANCE: This pilot study suggests that SCC at a level of (greater than or equal to) 250,000 cells mL-1, as used in the dairy industry, is a suitable index to identify asymptomatic subclinical mastitis in lactating women since it reflects a significant increase in the inflammatory response compared to milk samples from healthy women. Using this index should aid studies into the short- and long-term consequences of subclinical mastitis for mother and infant.

Quantification of ADHD medication in biological fluids of pregnant and breastfeeding women with liquid chromatography: a comprehensive review.

Attention Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that has long been considered a concern only in the pediatric population. However, symptoms often sustain into adulthood and may require medication. For women with ADHD, this also means dealing with the disorder during the reproductive period. Medication safety during pregnancy and breastfeeding is a critical concern, and the potential transfer of ADHD medication to infants remains a topic of scientific interest. The quantification of ADHD medications in both maternal blood and breast milk are vital for understanding their pharmacokinetics and potential exposure risks for (nursing) infants. This review aims (1) to compile and critically assess existing research on the transfer of ADHD medications into breast milk and the potential implications for nursing infants and (2) to provide a comprehensive overview and discussion of the literature regarding the quantification of methylphenidate, amphetamine, atomoxetine, viloxazine, guanfacine, clonidine and bupropion in the blood, urine, oral fluid, and breast milk with liquid chromatography. A literature search was conducted using PubMed, Scopus, and Web of Science, to identify relevant articles published from January 2014 up to December 2023. We illustrate the lack of methods to simultaneously monitor multiple ADHD medications as well as the lack of developed methods for breast milk. Finally, we highlight the need for continued research to refine our understanding of medication transfer into breast milk and potential risks, and to develop clinical guidelines to support mothers with ADHD in making informed choices regarding medication use during pregnancy and lactation.

Development and clinical implementation of an LC-HRMS method for ivacaftor, lumacaftor, tezacaftor and elexacaftor in human plasma and breast milk.

The four cystic fibrosis (CF) transmembrane conductance regulator (CFTR) modulators, ivacaftor, lumacaftor, tezacaftor, and elexacaftor, have revolutionised the treatment of CF by direct action on the protein target behind the disease's development. The aim was to develop and validate a quantification method for these CFTR modulators in plasma and breast milk to better understand inter-patient variability in pharmacokinetics and treatment outcome, including the risk of adverse drug reactions. The ability to monitor CFTR modulators in breast milk enables the estimation of the exposure of breastfed infant, with a potential concern for CFTR modulator-induced liver injury. The analysis was performed on a Thermo Vanquish Flex Binary UHPLC system coupled to a high-resolution mass spectrometer (HRMS), Thermo Q Exactive. The analytes were detected using positive electrospray ionisation in full scan mode. After sample preparation by protein precipitation, the supernatant was injected onto the LC system and the analytes were separated using a Zorbax SB-C18 Rapid Res HPLC column (3.5 µm, 4.6 × 75 mm). This is the first published method for CFTR modulators in breast milk. The validated quantification range for ivacaftor is 0.0050-10 µg/mL with a coefficient of variation < 6% and a mean accuracy of 97-106%; for lumacaftor, tezacaftor, and elexacaftor, the validated quantification range is 0.050-100 µg/mL with a coefficient of variation < 8% and a mean accuracy 93-106%. A simple and sensitive quantification method for CFTR modulators has been developed and used for routine analysis of human plasma and breast milk samples since 2022.

Breast milk induces the differentiation of monocytes into macrophages, promoting human cytomegalovirus infection.

Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus found in human breast milk that is frequently transmitted from HCMV-seropositive mothers to their infants during the postnatal period. Despite extensive research, the mechanisms underlying HCMV transmission from breast milk and the anatomical location at which virus transfer takes place remain unclear. Breast milk contains many uniquely differentiated macrophages that undergo specific morphological and functional modifications in the mammary gland during lactation. Although the existence of permissive HCMV infection in differentiated macrophages has been well-described, the role of breast milk in this process remains unknown. Herein, we report that exposure of isolated peripheral blood monocytes to breast milk induces their differentiation into macrophages that exhibit an M2 phenotype (CD14highCD163highCD68highCD206high) and promotes a productive and sustained HCMV infection. We also found that breast milk triggers macrophage proliferation and thus sustains a unique population of proliferating, long-lived, and HCMV-susceptible macrophages that are capable of ongoing production of infectious virions. These results suggest a mechanism that explains chronic HCMV shedding into the breast milk of postpartum seropositive mothers. We also found that HCMV virions released from breast milk-induced macrophages generate a productive infection in primary infant tonsil epithelial cells. Collectively, our results suggest that breast milk may facilitate HCMV transmission from mother to infant via the oropharyngeal mucosa. IMPORTANCE: While human cytomegalovirus (HCMV) is frequently detected in the breast milk of HCMV-seropositive women and is often transmitted to infants via breastfeeding, the mechanisms by which this transmission occurs remain unclear. In this study, we modeled HCMV transmission at the oropharyngeal mucosa. We treated human monocytes with breast milk to mimic the lactating mammary gland microenvironment. We found that monocytes differentiated into macrophages with an M2 phenotype, which were highly permissive for HCMV. We also discovered that breast milk induces macrophage proliferation. Thus, exposure to breast milk increased the number of HCMV-susceptible macrophages and supported high levels of infectious HCMV. We found that HCMV virions released from breast milk-induced macrophages could infect primary infant tonsil epithelial cells. Collectively, these findings reveal the dual role of breast milk that induces the differentiation and proliferation of macrophages in the mammary gland and thus facilitates mother-to-child HCMV transmission at the oropharyngeal mucosa.

Comparison of prenatal and postnatal exposure to neonicotinoids and their temporal trends in breast milk.

Although the potential effects of neonicotinoids (NEOs) in early life have received considerable attention, data on the exposure of mothers and infants to NEOs are scarce. In this study, four parent NEOs and one metabolite were widely detected in paired maternal serum (MS), umbilical cord serum (UCS) and breast milk (BM) samples, with median total NEO concentrations (ΣNEOs) of 113, 160 and 69 ng/L, respectively. Decreasing trends were observed for N-desmethyl-acetamiprid (30 %/year), acetamiprid (22 %/year) and ΣNEOs (15 %/year) in breast milk between 2014 and 2022, whereas increasing trends were seen for clothianidin (17 %/year) and thiamethoxam (30 %/year). N-desmethyl-acetamiprid was the predominant compound in all matrices. However, the contributions of N-desmethyl-acetamiprid (35 %) and thiamethoxam (36 %) in breast milk were similar in 2022. Moreover, thiamethoxam has become the predominant contributor to the estimated daily intake of ΣNEOs since 2018, with the highest contribution of 71 % in 2022, suggesting the effects of NEOs continue to evolve and more attention should be paid to the new NEOs. Notably, the correlations and ratios of NEOs between paired UCS and MS were more significant and higher than those between paired BM and MS, respectively, indicating that NEO exposure was largely affected by the prenatal period.

Assessing immune factors in maternal milk and paired infant plasma antibody binding to human rhinoviruses.

Introduction: Before they can produce their own antibodies, newborns are protected from infections by transplacental transfer of maternal IgG antibodies and after birth through breast milk IgA antibodies. Rhinovirus (RV) infections are extremely common in early childhood, and while RV infections often result in only mild upper respiratory illnesses, they can also cause severe lower respiratory illnesses such as bronchiolitis and pneumonia. Methods: We used high-density peptide arrays to profile infant and maternal antibody reactivity to capsid and full proteome sequences of three human RVs - A16, B52, and C11. Results: Numerous plasma IgG and breast milk IgA RV epitopes were identified that localized to regions of the RV capsid surface and interior, and also to several non-structural proteins. While most epitopes were bound by both IgG and IgA, there were several instances where isotype-specific and RV-specific binding were observed. We also profiled 62 unique RV-C protein loop sequences characteristic of this species' capsid VP1 protein. Discussion: Many of the RV-C loop sequences were highly bound by IgG from one-year-old infants, indicating recent or ongoing active infections, or alternatively, a level of cross-reactivity among homologous RV-C sites.

Donor Milk Expression Habits: Can we Favor Hindmilk Banking for Extremely Preterm Infants?

Background: Extremely preterm infants often receive donor milk. Hindmilk, which is released more than 3 minutes after letdown, could be advantageous due to its elevated levels of fat and calorie density. Donor milk expression habits may influence milk composition but have not yet been investigated. This study aims to assess the practices of milk donors and the feasibility of hindmilk expression. Methods: Active milk donors in Québec were questioned using an online survey about their milk expression habits and whether hindmilk donation would be acceptable to them. Answers were analyzed using mixed methods. Results: Of 181 donors, 126 fully completed the questionnaire (70%); 57% reported expressing donated milk between breastfeeds; 15% reported simultaneously breastfeeding while expressing donated milk from the other breast; 12% reported breastfeeding their baby on each breast, then expressing donated milk (hindmilk). The majority (66%) would be willing to change their habits most or all the time to provide hindmilk for preterm infants. The main themes invoked by respondents in open-ended answers were altruism and gratitude for being able to help others. However, 15% commented on the complexity of milk expression or that adding further complexity might discourage them from donating. Conclusions: Expression practices are variable, which may lead to variability in donor milk composition. Most donors would agree to change their expression habits in favor of giving hindmilk to help the most fragile infants. More information is needed on how changing recommendations for milk expression might impact the supply and composition of donor milk.

Validated UPLC-MS/MS method for quantification of melatonin receptor agonists and dual orexin receptor antagonists in human plasma and breast milk: Application to quantify suvorexant and lemborexant in clinical samples.

Pharmaceutical care is important for mental health during the perinatal period, which is often characterized by insomnia. In recent years, prescriptions of melatonin receptor agonists (MRAs) and dual orexin receptor antagonists (DORAs) for insomnia have increased; however, their use during the perinatal period has scarcely been reported. In the present study, we developed a UPLC-MS/MS method for the quantification of ramelteon, its metabolite M-II, suvorexant, and lemborexant in human plasma and breast milk to accumulate information on the safety and transfer of MRAs and DORAs into breast milk. Samples of MRAs (ramelteon and M-II) in plasma and breast milk were prepared using liquid-liquid extraction (LLE) with ethyl acetate. For DORAs (suvorexant and lemborexant), LLE with ethyl acetate was applied to plasma samples. For breast milk samples, significant ion suppression was observed for LLE with ethyl acetate. Solid-phase extraction (SPE) cartridges capable of removing phospholipids improved the matrix effects. Finally, protein precipitation with methanol and an SPE cartridge, InertSep® Phospholipid Remover, were selected for breast milk sample preparation. An ACQUITY UPLC BEH C18 column was used for analyte separation. MRAs and DORAs were eluted using isocratic and gradient elution, respectively, and analyzed using electrospray ionization in the positive mode with multiple reaction monitoring. The range of calibration curve for MRAs and DORAs was 0.1-25 and 0.5-50 ng/ml, respectively. Both the plasma and breast milk samples exhibited good linearity over this range. The method was validated by evaluating its accuracy and precision, matrix effect, recovery, carry-over, stability, and dilution integrity. The validated method was successfully applied to clinical samples donated by breastfeeding women and the milk/plasma (M/P) ratio and relative infant dose (RID) of lemborexant (one case) and suvorexant (two cases) were estimated. The M/P ratio of lemborexant was <1, and the RID was 1.05 %. The M/P ratio of suvorexant was <0.1, and RID was 0.11-0.20 %. This method will be useful for future studies evaluating the safety of these drugs during breastfeeding.

Importance of Human Breast Milk in the Early Colonization of Streptococcus mutans.

Background and objectives: The development of the oral microbiome begins in the prenatal stage. Breast milk contains antimicrobial proteins, microorganisms, metabolites, enzymes, and immunoglobulins, among others; therefore, differences have been noted in the type of microorganisms that colonize the oral cavity of children who are breastfed compared to those who are formula-fed. Our objective was to establish the relationship between breastfeeding, formula feeding, or mixed feeding (breastfeeding and formula) with the presence of S. mutans in a population of children under 6 months of age. Materials and Methods: The patients were recruited from the Child Care Center of Ciudad Juárez, Chihuahua, and from the pediatric dentistry postgraduate clinics of the Autonomous University of Ciudad Juárez; children exclusively fed maternally, with formula, and/or mixed were included. Those who had been fed within the previous hour were excluded. The sample was taken with a smear of the jugal groove using a sterile micro-brush. For the identification of Streptococcus mutans, a culture of Mitis Salivarius Agar (Millipore) was used. Results: 53.3% corresponded to females and 46.7% to males, 36.7% corresponded to maternal feeding, 23.3% corresponded to formula feeding, and 40% corresponded to mixed feeding. In 90% of the infants, the parents indicated that they did not perform oral hygiene. The CFU count showed that infants who were exclusively breastfed had an average of 9 × 10 CF/mL, formula-fed infants had an average of 78 × 10 CFU/mL, and those who had mixed feeding 21 × 10 CFU/mL. Conclusions: According to the results obtained, it was possible to corroborate that exclusive breastfeeding limits the colonization of Streptococcus mutans compared to those infants who receive formula or mixed feeding; these results could have a clinical impact on the dental health of infants by having a lower presence of one of the main etiological factors involved in dental caries and the type of microbiome established in the oral cavity.

Experiences of breast milk donors in Sweden: balancing the motivation to do something good with overcoming the challenges it entails.

BACKGROUND: Infants requiring neonatal care often face initial breastfeeding challenges, leading them to receive expressed breast milk from their mother or donor milk. While emphasizing the mother's own milk as the gold standard for infant nutrition, the utilization of donor milk stands as the preferred alternative over infant formula due to its numerous benefits. To facilitate the provision of donor milk to preterm and ill infants in neonatal units, the active participation of women willing to contribute their breast milk is crucial. This study aims to enhance the understanding of women's experiences in the donation process, thereby contributing to efforts aiming at alleviating the shortage of donated breast milk by improve the care and support for breast milk donors. METHODS: This descriptive qualitative study took an inductive approach based on individual semi-structured interviews conducted during 2021 with 15 breast milk donors in Sweden. The data were analysed with thematic analysis. RESULTS: Two themes were identified in the analysis: motivation to donate and challenges to overcome. Many of the women struggled to overcome the apparent challenges of not only starting the process of donating breast milk but also maintaining it. Despite the strain, they were motivated to donate their breast milk and seeking information by themselves to do something important for someone else. Only a few of the women talked about the financial benefits of donating breast milk; donating seemed to be mostly based on altruistic reasons. CONCLUSIONS: Despite the challenges posed by COVID-19 restrictions, time consumption, and the hard work of sterilizing pump utensils, women continued to donate their milk driven by altruism. To enhance donor support and increase milk donation, several improvements are suggested: providing comprehensive information and resources, simplifying the donation process, offering flexible scheduling, and recognizing donors' contributions.

Development of systemic and mucosal immune responses against gut microbiota in early life and implications for the onset of allergies.

The early microbial colonization of human mucosal surfaces is essential for the development of the host immune system. Already during pregnancy, the unborn child is prepared for the postnatal influx of commensals and pathogens via maternal antibodies, and after birth this protection is continued with antibodies in breast milk. During this critical window of time, which extends from pregnancy to the first year of life, each encounter with a microorganism can influence children's immune response and can have a lifelong impact on their life. For example, there are numerous links between the development of allergies and an altered gut microbiome. However, the exact mechanisms behind microbial influences, also extending to how viruses influence host-microbe interactions, are incompletely understood. In this review, we address the impact of infants' first microbial encounters, how the immune system develops to interact with gut microbiota, and summarize how an altered immune response could be implied in allergies.

Biological clock and circadian rhythm of breast milk composition.

Breast milk provides numerous benefits for both the baby and the mother, making it a unique and valuable food. The World Health Organization and the United Nations International Children's Emergency Found (UNICEF) state that exclusive breastfeeding in the first six months of life is an important strategy for reducing mortality and morbidity in infants. The circadian rhythm formation, which starts in the mother's womb, continues after the baby is born. Breast milk plays an active role in regulating the baby's circadian rhythm through the hormones, basic immune factors and bioactive components it contains, as well as meeting almost all nutritional elements for babies. Since the neural control mechanisms in the newborn are not yet fully developed, breast milk undertakes the task of helping the biological rhythms in the regulation of the infant's sleep-wake cycles, thanks to the circadian rhythm of some elements in its composition. There are studies showing that breast milk contains high levels of cortisol and amino acids that promote activity during the day, while night milk has high levels of melatonin and tryptophan, and micronutrients vary throughout the day. A better understanding of the circadian rhythm displayed by the elements in the composition of breast milk is important for improving maternal and infant health. Since there are many factors affecting the composition of breast milk, it is recommended that breast milk studies should be done on a country or regional basis, and breastfeeding policies can be developed as a result of the results to be obtained.

Screening for compounds with bioaccumulation potential in breast milk using their retention behavior in two-dimensional gas chromatography.

Discovery of emerging pollutants in breast milk will be helpful for understanding the hazards to human health. However, it is difficult to identify key compounds among thousands present in complex samples. In this study, a method for screening compounds with bioaccumulation potential was developed. The method can decrease the number of compounds needing structural identification because the partitioning properties of bioaccumulative compounds can be mapped onto GC×GC chromatograms through their retention behaviors. Twenty pooled samples from seven provinces in China were analyzed. 1,286 compounds with bioaccumulation potential were selected from over 3,000 compounds. Sixty-two compounds, including aromatic compounds, phthalates, and phenolics etc., were identified with a high level of confidence and then quantified. Among them, twenty-seven compounds were found for the first time in breast milk. Three phthalate plasticizers and two phenolic antioxidants were found in significantly higher concentrations than other compounds. A toxicological priority index approach was applied to prioritize the compounds considering their concentrations, detection frequencies and eight toxic effects. The prioritization indicated that 13 compounds, including bis(2-ethylhexyl) phthalate, dibutyl phthalate, 1,3-di-tert-butylbenzene, phenanthrene, 2,6-di-tert-butyl-1,4-benzoquinone, 2,4-di-tert-butylphenol, and others, showed higher health risks. Meanwhile, some compounds with high risk for a particular toxic effect, such as benzothiazole and geranylacetone, were still noteworthy. This study is important for assessing the risks of human exposure to organic compounds.

Physiology of Human Lactation and Strategies to Support Milk Supply for Breastfeeding.

Despite advances across the globe in breastfeeding initiation rates, many families continue to report they are not meeting their breastfeeding goals. Concerns about milk supply, infant nutritional intake, and infant weight gain are among the most commonly cited reasons for early breastfeeding cessation. Nurses working with individuals during the perinatal period are uniquely positioned to educate families and offer evidence-based interventions to promote optimal milk supply, infant growth, and maternal mental and physical health. Such interventions include early and frequent skin-to-skin care, emptying of the breast, and professional lactation support. By implementing such evidence-based practices in the first hours after birth and connecting families to lactation support in the first 14 days, nurses can begin to help families achieve their breastfeeding goals.

Protection from environmental enteric dysfunction and growth improvement in malnourished newborns by amplification of secretory IgA.

Environmental enteric dysfunction (EED) is a condition associated with malnutrition that can progress to malabsorption and villous atrophy. Severe EED results in linear growth stunting, slowed neurocognitive development, and unresponsiveness to oral vaccines. Prenatal exposure to malnutrition and breast feeding by malnourished mothers replicates EED. Pups are characterized by deprivation of secretory IgA (SIgA) and altered development of the gut immune system and microbiota. Extracellular ATP (eATP) released by microbiota limits T follicular helper (Tfh) cell activity and SIgA generation in Peyer's patches (PPs). Administration of a live biotherapeutic releasing the ATP-degrading enzyme apyrase to malnourished pups restores SIgA levels and ameliorates stunted growth. SIgA is instrumental in improving the growth and intestinal immune competence of mice while they are continuously fed a malnourished diet. The analysis of microbiota composition suggests that amplification of endogenous SIgA may exert a dominant function in correcting malnourishment dysbiosis and its consequences on host organisms, irrespective of the actual microbial ecology.

The association between maternal factors and milk hormone concentrations: a systematic review.

Background: Breast milk is the gold standard for infant feeding. It is a dynamic biological fluid rich in numerous bioactive components. Emerging research suggests that these components, including hormones, may serve as signals between mother and offspring. From an evolutionary perspective, maternal hormonal signals could allow co-adaptation of maternal and offspring phenotype, with implications for their Darwinian fitness. However, a series of steps need to be considered to establish the role of a component as a signal and this systematic review focuses on one step: 'Do maternal factors influence the concentration of milk hormones?' Objective: To systematically review human studies which analyze the association between maternal factors and the concentration of hormones in breast milk. Methods: Three databases were searched for studies reporting the association of maternal factors including body mass index (BMI), weight, fat mass, age, ethnicity, smoking with hormones such as adiponectin, leptin, insulin, ghrelin, and cortisol in breast milk. Results: Thirty-three studies were eligible for inclusion. Maternal BMI was positively associated with milk leptin (20/21 studies) and with milk insulin (4/6 studies). Maternal weight also displayed a positive correlation with milk leptin levels, and maternal diabetes status was positively associated with milk insulin concentrations. Conversely, evidence for associations between maternal fat mass, smoking, ethnicity and other maternal factors and hormone levels in breast milk was inconclusive or lacking. Conclusion: Current evidence is consistent with a signaling role for leptin and insulin in breast milk, however other steps need to be investigated to understand the role of these components as definitive signals. This review represents a first step in establishing the role of signaling components in human milk and highlights other issues that need to be considered going forward.

Mother's Milk Donation to a Human Milk Bank During Bereavement: Circumstances Associated with Completing the Donation Process.

Background: Bereaved mothers describe positive experiences donating breast milk and negative experiences when not informed of opportunities to donate. Predictors of whether mothers donate milk are unknown, impairing efforts to optimize support in completing donation. Objective: To define circumstances associated with completing mother's milk (MM) donation during bereavement. Methods: A retrospective cohort study included dyads of bereaved mothers and their deceased children if a child's death occurred on-site at a quaternary care children's hospital during 2016-2020, the child had documentation of MM availability, and age at death <24 months. The primary outcome was the completion of MM donation to the milk bank. Multivariate logistic regression measured associations between clinical variables and odds of completion. Results: Of 124 deceased children with documented MM exposure, 34 mothers (28%) of 35 of those children completed MM donation, donating a mean of 13.7 liters (SD 16.8). The child's race/ethnicity documented in the medical record was White for 25 (71%), Black/African American (AA) for 1 (3%), Asian for 1 (3%), and Hispanic/Latino for 8 (23%). Referenced to mothers of White children, being a mother of an AA [OR 0.05 (95% CI: 0.01-0.43)] or Asian [0.08 (0.01-0.75)] child was associated with lower odds of donation. Referenced to mothers delivering full term (≥37 weeks'), mothers delivering <34 weeks showed higher odds [5.0 (1.5-17.5)] of donation. Conclusion: Relatively few bereaved mothers of children with indicators of MM exposure completed donation. The results suggest an opportunity to ensure bereaved mothers are uniformly informed and supported in donating.