Nutritional and immunological factors in breast milk: A role in the intergenerational transmission from maternal psychopathology to child development

Maternal stress is associated with higher protein-bound amino acid concentrations in human milk

Background

Maternal stress in the postpartum period affects not only the mother but also her newborn child, who is at increased risk of developing metabolic and mental disorders later in life. The mechanisms by which stress is transmitted to the infant are not yet fully understood. Human milk (HM) is a potential candidate as maternal stress affects various components of HM, e.g., fat and immunoglobulin concentrations. To date, it is unknown whether maternal stress also affects the amino acids (AAs) in HM, even though this nutrient is of extreme importance to child health and development. This study aimed to investigate whether and how maternal stress is associated with the AA composition of HM.

Methods

In this observational cohort study (Amsterdam, The Netherlands), lactating women were recruited in two study groups: a high-stress (HS) group; women whose child was hospitalized (n = 24), and a control (CTL) group; women who gave birth to a healthy child (n = 73). HM was collected three times a day, on postpartum days 10, 17, and 24. Perceived psychological stress was measured using validated questionnaires, while biological stress measures were based on hair, saliva, and HM cortisol concentrations. HM protein-bound and free AAs were analyzed by liquid chromatography and compared between groups.

Results

Maternal perceived stress scores were higher in the HS group (p < 0.01). The concentrations of protein-bound AAs in HM were higher in the HS group compared to the CTL group (p = 0.028) and were positively associated with HM cortisol concentrations (p = 0.024). The concentrations of free AAs did not differ between study groups and were unrelated to cortisol concentrations.

Conclusion

Findings from this prospective cohort study suggest that maternal stress in the postpartum period is associated with an altered human milk amino acid composition, which could play a role in the transmission of maternal stress effects to her child. The physiological implications of these stress-induced changes for infant development await future research.

Collaborating to Improve Neonatal Care: ParentAl Participation on the NEonatal Ward-Study Protocol of the neoPARTNER Study

Parents are often appointed a passive role in the care for their hospitalised child. In the family-integrated care (FICare) model, parental involvement in neonatal care is emulated. Parental participation in medical rounds, or family-centred rounds (FCR), forms a key element. A paucity remains of randomised trials assessing the outcomes of FCR (embedded in FICare) in families and neonates, and outcomes on an organisational level are relatively unexplored. Likewise, biological mechanisms through which a potential effect may be exerted are lacking robust evidence. Ten level two Dutch neonatal wards are involved in this stepped-wedge cluster-randomised trial FCR (embedded in FICare) by one common implementation strategy. Parents of infants hospitalised for at least 7 days are eligible for inclusion. The primary outcome is parental stress (PSS:NICU) at discharge. Secondary outcomes include parental, neonatal, healthcare professional and organisational outcomes. Biomarkers of stress will be analysed in parent-infant dyads. With a practical approach and broad outcome set, this study aims to obtain evidence on the possible (mechanistic) effect of FCR (as part of FICare) on parents, infants, healthcare professionals and organisations. The practical approach provides (experiences of) FICare material adjusted to the Dutch setting, available for other hospitals after the study.

Prebiotic and Probiotic Modulation of the Microbiota-Gut-Brain Axis in Depression

Emerging evidence demonstrates that alterations to the gut microbiota can affect mood, suggesting that the microbiota-gut-brain (MGB) axis contributes to the pathogenesis of depression. Many of these pathways overlap with the way in which the gut microbiota are thought to contribute to metabolic disease progression and obesity. In rodents, prebiotics and probiotics have been shown to modulate the composition and function of the gut microbiota. Together with germ-free rodent models, probiotics have provided compelling evidence for a causal relationship between microbes, microbial metabolites, and altered neurochemical signalling and inflammatory pathways in the brain. In humans, probiotic supplementation has demonstrated modest antidepressant effects in individuals with depressive symptoms, though more studies in clinically relevant populations are needed. This review critically discusses the role of the MGB axis in depression pathophysiology, integrating preclinical and clinical evidence, as well as the putative routes of communication between the microbiota-gut interface and the brain. A critical overview of the current approaches to investigating microbiome changes in depression is provided. To effectively translate preclinical breakthroughs in MGB axis research into novel therapies, rigorous placebo-controlled trials alongside a mechanistic and biochemical understanding of prebiotic and probiotic action are required from future research.

Mechanisms of Maternal Diet-Induced Obesity Affecting the Offspring Brain and Development of Affective Disorders

Depression and metabolic disease are common disorders that share a bidirectional relationship and continue to increase in prevalence. Maternal diet and maternal behaviour both profoundly influence the developmental trajectory of offspring during the perinatal period. At an epidemiological level, both maternal depression and obesity during pregnancy have been shown to increase the risk of neuropsychiatric disease in the subsequent generation. Considerable progress has been made to understand the mechanisms by which maternal obesity disrupts the developing offspring gut-brain axis, priming offspring for the development of affective disorders. This review outlines such mechanisms in detail, including altered maternal care, the maternal microbiome, inflammation, breast milk composition, and maternal and placental metabolites. Subsequently, offspring may be prone to developing gut-brain interaction disorders with concomitant changes to brain energy metabolism, neurotransmission, and behaviour, alongside gut dysbiosis. The gut microbiome may act as a key modifiable, and therefore treatable, feature of the relationship between maternal obesity and the offspring brain function. Further studies examining the relationship between maternal nutrition, the maternal microbiome and metabolites, and offspring neurodevelopment are warranted to identify novel therapeutic targets.

The metabolome of human milk is altered differentially by Holder pasteurization and high hydrostatic pressure processing

The milk metabolome is composed of hundreds of molecules that can impact infant development. In preterm infants, sterilized donor milk (DM) is frequently used for their feeding. We aimed to identify differences in the metabolome of DM after two types of milk sterilization: the Holder pasteurization (HoP) and a high hydrostatic pressure (HP) processing. DM samples were sterilized by HoP (62.5°C for 30 min) or processed by HP (350 MPa at 38°C). 595 milk metabolites were analyzed using an untargeted metabolomic analysis. Both treatments differentially altered several classes of compounds. The major changes noted included decreased levels of free fatty acids, phospholipid metabolites, and sphingomyelins. Decreases were more strongly noted in HP samples rather than in HoP ones. Both HoP and HP treatments increased the levels of ceramides and nucleotide compounds. The sterilization of human milk altered its metabolome especially for lipids.

Process and effect evaluation of the app-based parenting program Samen Happie! on infant zBMI: A randomized controlled trial

Background

Although energy balance-related parenting practices are regarded critical components in the prevention of childhood obesity, most programs targeting parenting practices with respect to a wide range of energy balance-related behaviors were not aimed at high-risk families with a lower socioeconomic position (SEP).

Objective

The Samen Happie! app-based program aimed to stimulate healthy child weight development especially among families with a lower SEP, by encouraging healthy energy balance-related parenting practices.

Methods

A two-armed randomized controlled trial examined the process and effectiveness of the Samen Happie! program on child zBMI outcomes at 6- and 12-months follow-up. In total, 357 Dutch parents with infants aged 5-15 months old at baseline participated. Parents in the app condition (n = 179) received access to the Samen Happie! app and were compared to a waitlist-control condition (n = 178). Changes in zBMI were examined through linear mixed-effects models based on intention-to-treat and exploratory per-protocol principles.

Results

Process data showed low levels of sustained app use and moderate app acceptability. A general increase in child zBMI was observed in both conditions after 6 and 12 months. Intention-to-treat analyses using multiple imputations showed several statistically significant differences between conditions and high-risk subgroups. Specifically, at 6-months follow-up, zBMI increase was least pronounced in the app condition among children of parents with lower educational level. These findings were supported by exploratory per-protocol analyses including only frequent app users. In addition, per-protocol analyses showed benefits of app use at 6-months follow-up for children of parents with higher BMI. However, these effects were reversed at 12-months follow-up in both intention-to-treat and per-protocol analyses, where children of parents in the app condition in general increased the most in zBMI.

Conclusions

This study suggests that the Samen Happie! program might prevent zBMI increases after 6 months among children of parents with lower educational level, and children of parents with higher BMI who more frequently use the app. However, the app did not prevent increases in zBMI after 12 months. Future research should investigate strategies to increase sustained app use and engagement in mHealth parenting programs for childhood obesity as well as options to combine app-based programs with additional support strategies aimed at high-risk families.

Trial registration

Netherlands trial register (ID: NTR6938), https://trialsearch.who.int/Trial2.aspx?TrialID=NTR6938.

Got milk? Maternal immune activation during the mid-lactational period affects nutritional milk quality and adolescent offspring sensory processing in male and female rats

Previous studies have underscored the importance of breastfeeding and parental care on offspring development and behavior. However, their contribution as dynamic variables in animal models of early life stress are often overlooked. In the present study, we investigated how lipopolysaccharide (LPS)-induced maternal immune activation (MIA) on postnatal day (P)10 affects maternal care, milk, and offspring development. MIA was associated with elevated milk corticosterone concentrations on P10, which recovered by P11. In contrast, both milk triglyceride and percent creamatocrit values demonstrated a prolonged decrease following inflammatory challenge. Adolescent MIA offspring were heavier, which is often suggestive of poor early life nutrition. While MIA did not decrease maternal care quality, there was a significant compensatory increase in maternal licking and grooming the day following inflammatory challenge. However, this did not protect against disrupted neonatal huddling or later-life alterations in sensorimotor gating, conditioned fear, mechanical allodynia, or reductions in hippocampal parvalbumin expression in MIA offspring. MIA-associated changes in brain and behavior were likely driven by differences in milk nutritional values and not by direct exposure to LPS or inflammatory molecules as neither LPS binding protein nor interleukin-6 milk levels differed between groups. These findings reflected comparable microbiome and transcriptomic patterns at the genome-wide level. Animal models of early life stress can impact both parents and their offspring. One mechanism that can mediate the effects of such stressors is changes to maternal lactation quality which our data show can confer multifaceted and compounding effects on offspring physiology and behavior.

Maternal Distress during Pregnancy and the Postpartum Period: Underlying Mechanisms and Child's Developmental Outcomes-A Narrative Review

Maternal mental health may be considered a determining factor influencing fetal and child development. An essential factor with potentially negative consequences for a child's psychophysiological development is the presence of maternal distress during pregnancy and the postpartum period. The review is organized and presented to explore and describe the effects of anxiety, stress, and depression in pregnancy and the postpartum period on adverse child developmental outcomes. The neurobiology of maternal distress and the transmission mechanisms at the molecular level to the fetus and child are noted. In addition, the paper discusses the findings of longitudinal studies in which early child development is monitored concerning the presence of maternal distress in pregnancy and the postpartum period. This topic gained importance in the COVID-19 pandemic context, during which a higher frequency of maternal psychological disorders was observed. The need for further interdisciplinary research on the relationship between maternal mental health and fetal/child development was highlighted, especially on the biological mechanisms underlying the transmission of maternal distress to the (unborn) child, to achieve positive developmental outcomes and improve maternal and child well-being.

Maternal stress in the postpartum period is associated with altered human milk fatty acid composition

BACKGROUND & AIMS

Maternal stress in the postpartum period affects not only the mother, but also her newborn child who is at increased risk for a wide range of disorders later in life. The mechanisms underlying transmission of maternal stress to the child remain elusive. Human milk (HM) is a potential candidate and is an important source of fatty acid (FA), which are crucial for child (neuro)development. This study aims to investigate whether maternal psychological and biological stress influences HM FA composition over the first month postpartum.

METHODS

The Amsterdam Mother's Milk study is a prospective cohort study. We included lactating women who delivered at term with a large range of stress levels: a high stress (HS) group, women whose child was hospitalized for a minimum of 2 days (n=23) and a control (CTL) group, women who gave birth to a healthy child (n=73). HM was collected three times a day at postpartum days 10, 17 and 24. Perceived psychological stress was measured using multiple validated questionnaires, while biological stress measures were based on cortisol in hair, saliva and HM. HM FAs were analyzed by gas-chromatography and compared between groups.

RESULTS

Maternal perceived stress scores were significantly higher in the HS group (p < 0.01), whereas cortisol measurements did not differ between groups. The absolute concentrations of total FA in HM (p=0.023), including the total amount of poly unsaturated fatty acids (PUFAs) (p=0.022) and omega-6 PUFAs (p=0.018), were lower in the HS group compared to the CTL group. Relative values of FAs did not differ between groups.

CONCLUSION

Maternal stress in the first month postpartum was associated with overall lower levels of FA in HM. This possibly indicates a route of transmission of maternal stress signals to the infant. Future research should investigate if these stress-induced changes in HM FAs have consequences for child development.

Association of Infant Feeding Indicators and Infant Feeding Practices with Coexisting Forms of Malnutrition in Children under Six Months of Age

Breastmilk is the only recommended source of nutrition for infants below six months of age. However, a significant proportion of children are either on supplemental breastfeeding (SBF) or weaned due to the early introduction of solid/semi-solid/soft food and liquids (SSF) before six months of age. There is good evidence that exclusive breastfeeding (EBF) in infants below six months of age protects them from preventable illnesses, including malnutrition. The relationship between infant feeding practices and coexisting forms of malnutrition (CFMs) has not yet been explored. This study examined the association of different feeding indicators (continuation of breastfeeding, predominant feeding, and SSF) and feeding practices (EBF, SBF, and complete weaning) with CFM in infants aged below six months in Pakistan. National and regional datasets for Pakistan from the last ten years were retrieved from the Demographic Health Surveys (DHS) and UNICEF data repositories. In Pakistan, 34.5% of infants have some form of malnutrition. Among malnourished infants, 44.7% (~15.4% of the total sample) had a CFM. Continuation of breastfeeding was observed in more than 85% of infants, but less than a quarter were on EBF, and the rest were either SBF (65.4%) or weaned infants (13.7%). Compared to EBF, complete weaning increased the odds of coexistence of underweight with wasting, and underweight with both wasting and stunting by 1.96 (1.12–3.47) and 2.25 (1.16–4.36), respectively. Overall, breastfed children had lower odds of various forms of CFM (compared to non-breastfed), except for the coexistence of stunting with overweight/obesity. Continuation of any breastfeeding protected infants in Pakistan from various types of CFM during the first six months of life.

Perception of the Body Image in Women after Childbirth and the Specific Determinants of Their Eating Behavior: Cross-Sectional Study (Silesia, Poland)

Background: Episodes of loss of control over eating during pregnancy affect up to 36% of women during this period. Many women experience natural concerns about weight gain and body-shape changes during pregnancy and the postpartum period, and food cravings and fluctuations in eating patterns during these periods are physiological phenomena. However, pregnancy and the postpartum period may be an additional determinant of eating disorders. Women who perceive their own bodies as significantly deviating from the presented ideal are more likely to experience anxiety/anxiety related to it and also tend to exhibit abnormal eating behaviors. The perception of one’s body figure also plays an important role in maintaining psychological balance Aim: The aim of this study was to assess the perception of body image by postpartum women. The essence of the study was to see if there were psychomarkers associated with lack of control over eating, food restriction, and emotionally motivated eating in the study population. Material and methods: The study was conducted during the fall and winter of 2021. A total of 288 women participated in the study. The age of the subjects ranged from 21 to 45 years. Results: It was found that 198 women (68.8%) were dissatisfied with their current body weight and figure. Respondents with higher post-pregnancy body mass index showed dissatisfaction with their body shape (49.8%; H = 13.042; p = 0.001). Both body satisfaction and BMI level were significant components of the occurrence of pathological phenomena associated with the TFEQ-13 subscales (p < 0.05). Conclusions: Excessive focus on food restriction as well as lack of control over eating had some association with negative self-perception of body image, mainly in the form of body weight dissatisfaction. Eating behaviors showed an association with BMI level and weight satisfaction after pregnancy.

Maternal Mental Health in Late Pregnancy and Longitudinal Changes in Postpartum Serum Vitamin B-12, Homocysteine, and Milk B-12 Concentration Among Brazilian Women

Background

Little is known regarding the association between mental health distress during pregnancy and postpartum maternal serum biomarkers of vitamin B-12 status and milk B-12 concentration.

Objective

To evaluate the association between depressive and anxiety symptoms in the third trimester of pregnancy and changes in postpartum serum B-12, homocysteine, and B-12 milk concentration.

Methods

A total of 101 women (18–40 years) were studied in a prospective cohort with data at the third trimester of pregnancy (baseline) and three postpartum time-points (TPs): 2–8 days (TP1), 28–50 days (TP2), and 88-119 days (TP3) postpartum. B-12 concentrations in milk were measured by competitive chemiluminescent enzyme immunoassay at TP1, TP2, and TP3. Serum B-12 and homocysteine concentrations were evaluated at baseline, TP1, TP2, and TP3 by chemiluminescent immunoassays. Depressive and anxiety symptoms were measured with the Edinburgh Postnatal Depression Scale and the State-Trait Anxiety Inventory at baseline. Spearman's correlation test and multiple linear mixed-effect models were performed.

Results

The prevalence of depressive and anxiety state symptoms was 35.6 and 39.6% at baseline. High prevalence of low milk B-12 concentration (<310 pmol/L) were observed at TP1 (53.2%), TP2 (71.4%), and TP3 (71.1%). Women with anxiety symptoms at baseline presented higher median concentrations of serum homocysteine at TP1 and lower concentrations of serum and milk B-12 at TP2 compared with women without anxiety symptoms [8 (7; 9) vs. 6 (5; 8) and 266 (188; 369) vs. 332 (272; 413)]. Milk B-12 concentrations were positively and significantly correlated with maternal serum B-12 concentrations at different TP. Women with anxiety symptoms at baseline exhibited a decrease in daily postpartum homocysteine concentrations compared to women without anxiety symptoms (β = −0.002, SE = 0.001, p = 0.024).

Conclusion

Anxiety symptoms at the end of pregnancy were associated with longitudinal changes in maternal serum homocysteine concentrations during the first 3 months postpartum.

Prenatal LPS exposure increases hippocampus IL-10 and prevents short-term memory loss in the male adolescent offspring of high-fat diet fed dams

Lipopolysaccharide (LPS) tolerance can reduce the neuroinflammation caused by high fat maternal diets; however, there are no reports that have evaluated the effects of prenatal LPS exposure on the memories of the offspring of high-fat diet fed dams. This study evaluated the effects of prenatal LPS exposure on the inflammatory parameters and redox status in the brain, as well as the object recognition memory of adolescent offspring of Wistar rat dams that were treated with a high-fat diet during gestation and lactation. Female pregnant Wistar rats randomly received a standard diet (17.5% fat) or a high-fat diet (45.0% fat) during gestation and lactation. On gestation days 8, 10, and 12, half of the females in each group were intraperitoneally treated with LPS (0.1 mg.kg-1). After weaning, the male offspring were placed in cages in standard conditions, and at 6 weeks old, animals underwent the novel object recognition test (for short- and long-term memory). The offspring of the high-fat diet fed dams showed increased hippocampus IL-6 levels (21-days-old) and impaired short-term memories. These effects were avoided in the offspring of high-fat diet fed dams submitted to prenatal LPS exposure, which showed greater hippocampus IL-10 levels (at 21- and 50-days-old), increased antioxidant activity (50-days-old) in the hippocampus and prefrontal cortex, without memory impairments (short- and long-term memory). IL-6 has been consistently implicated in memory deficits and as an endogenous mechanism for limiting plasticity, while IL-10 regulates glial activation and has a strong association with improvements in cognitive function. Prenatal LPS exposure preventing the increase of IL-6 in the hippocampus and the impairment to short-term object recognition memory caused by the high-fat maternal diet.

The role of inflammation in the pathogenesis of perinatal depression and offspring outcomes

The role of inflammation in the pathogenesis of depression is becoming increasingly apparent, but its role in perinatal depression is less well-studied. Pregnancy and the postpartum are characterised by distinct and changing inflammatory profiles throughout, which makes the study of depression-related alterations in this period complex. This review presents literature discussing a role for the immune system in both antenatal and postnatal depression. Furthermore, literature investigating the role of the maternal immune system on breast milk composition and offspring immunological and behavioural outcomes is discussed, before concluding with suggestions for future work as this developing field grows.

Human milk metabolome is associated with symptoms of maternal psychological distress and milk cortisol

The composition of human milk is subject to considerable variation, but the effects of maternal stress are largely unknown. We studied differences in human milk metabolome between Finnish mothers (n = 120, secretors) with symptoms of prenatal symptoms of psychological distress and milk cortisol concentrations. Human milk samples acquired at 2.5 months postpartum were analyzed using targeted ¹H NMR metabolomics. Self-reported scores for depression (EPDS), overall anxiety (SCL-90), and pregnancy-related anxiety (PRAQ) were used to evaluate psychological distress. Prenatal psychological distress was positively associated with concentrations of short-chain fatty acids, caprate, and hypoxanthine (q < 0.0012). Milk cortisol was positively associated with lactate concentration (q < 0.05). Changes in the human milk metabolome were shown to be associated with maternal psychological distress and concentration of milk cortisol in a dissimilarly, suggesting alterations in bacterial and energy metabolism of the mother, respectively.

Presence of Ebola virus in breast milk and risk of mother-to-child transmission: synthesis of evidence

To help inform global guidelines on infant feeding, this systematic review synthesizes evidence related to the presence of the Ebola virus (EBOV) in breast milk and its potential risk of viral transmission to the infant when breastfeeding. We relied on a comprehensive search strategy to identify studies including women with suspected, probable, or confirmed EBOV infection, intending to breastfeed or give breast milk to an infant. Our search identified 10,454 records, and after deduplication and screening, we assessed 148 full texts. We included eight studies reporting on 10 breastfeeding mothers and their children (one mother with twins), who provided breast milk samples for assessment. EBOV was detected via RT-PCR or viral culture in seven out of ten breast milk samples. Four out of the five-breastfed infants with EBOV-positive breast milk were found positive for EBOV infection, and all of these EBOV-positive infants died. Since previous reports have detected EBOV in tears, saliva, sweat, and contaminated surfaces, with the current evidence, it is not possible to conclude with certainty that breast milk was the main route of EBOV transmission.

Appearance of Acute Inflammatory State Indicates Improvement in Atopic Dermatitis Cases Under Classical Homeopathic Treatment: A Case Series

The Continuum theory and the Levels of Health theory propound the idea that return of efficient acute inflammation (high fever) heralds true improvement in chronic inflammatory states. We present 6 cases of atopic dermatitis (AD), which had stability in their improvement for 1 year or more, under classical homeopathy. The cases were retrospectively assessed with selected based on the Hanifin Rajka atopic dermatitis diagnostic criteria and the follow ups evaluated according to changes on SCORing Atopic Dermatitis scale (SCORAD) scale. The pictures are presented as evidence. Modified Naranjo Criteria for assessing causal attribution of clinical outcome to homeopathic intervention was used to assess the effect of homeopathy in these cases. All the cases improved and stabilised with complete skin clearance (those that relapsed within 1 year were not included). These patients had not suffered high fevers/acute inflammatory diseases since onset/aggravation of AD. Five of the 6 cases developed acute inflammatory diseases as the chronic condition improved. The last case showed return of an old, lesser pathology. The control cases – which were selected for non-improvement under classical homeopathy also showed remarkable skin clearance when there was appearance of acute inflammatory states. In this study, there is a mutually exclusive relationship between efficient acute inflammation and chronic inflammation, which is in accordance with the 2 theories considered here. Further scientific studies are necessary to establish the phenomenon at tissue level.

The Triad Mother-Breast Milk-Infant as Predictor of Future Health: A Narrative Review

The benefits of human milk for both mother and infant are widely acknowledged. Human milk could represent a link between maternal and offspring health. The triad mother-breast milk-infant is an interconnected system in which maternal diet and lifestyle might have effects on infant's health outcome. This link could be in part explained by epigenetics, even if the underlining mechanisms have not been fully clarified yet. The aim of this paper is to update the association between maternal diet and human milk, pointing out how maternal diet and lifestyle could be associated with breast-milk composition, hence with offspring's health outcome.

Priming for Life: Early Life Nutrition and the Microbiota-Gut-Brain Axis

Microbes colonize the human body during the first moments of life and coexist with the host throughout the lifespan. Intestinal microbiota and their metabolites aid in the programming of important bodily systems such as the immune and the central nervous system during critical temporal windows of development, with possible structural and functional implications throughout the lifespan. These critical developmental windows perinatally (during the first 1000 days) are susceptible timepoints for insults that can endure long lasting effects on the microbiota-gut-brain axis. Environmental and parental factors like host genetics, mental health, nutrition, delivery and feeding mode, exposure to antibiotics, immune activation and microbiota composition antenatally, are all factors that are able to modulate the microbiota composition of mother and infant and may thus regulate important bodily functions. Among all these factors, early life nutrition plays a pivotal role in perinatal programming and in the modulation of offspring microbiota from birth throughout lifespan. This review aims to present current data on the impact of early life nutrition and microbiota priming of important bodily systems and all the factors influencing the microbial coexistence with the host during early life development.

Associations between maternal socioeconomic, psychosocial and seasonal factors, infant characteristics and human milk cortisol concentrations

OBJECTIVES

Glucocorticoids are one component of human milk (HM) potentially affecting offspring development. Previous studies have identified various maternal, obstetric and socioeconomic characteristics that are associated with HM cortisol concentration but the literature is still scarce concerning these determinants in human populations. We aimed to identify which factors are linked with HM cortisol concentration at 2 months postpartum.

METHODS

We analyzed data from 340 lactating Finnish mothers using ordinary least squares regression with log-transformed HM cortisol concentration as the dependent variable. Potential predictors included obstetric and maternal factors (maternal age, parity status, delivery mode, gestational age, pre-pregnancy obesity, and smoking in pregnancy), socioeconomic status (education and socioeconomic class), subjective economic well-being, maternal psychosocial factors (postpartum depression and anxiety symptoms), infant sex and age, and HM sample characteristics (time of the day and season of the year at sample collection).

RESULTS

The strongest and most robust predictors were season of the year of sample collection and parity status. HM cortisol concentration was significantly higher for primiparas than multiparas. HM samples collected in summer showed significantly higher cortisol concentrations than those collected in winter, spring or autumn.

CONCLUSIONS

The findings suggest that parity and season of the year at sample collection may be important factors to control for when examining HM cortisol. The strongest and most robust associations were related to maternal and sample characteristics and not to socioeconomic and psychosocial distress. This may be related to the fact that the study was conducted in a low-risk population.

[Effect of omega-3 supplementation during pregnancy and lactation on the fatty acid composition of breast milk in the first months of life: a narrative review]

Introduction

Omega-3 long-chain, polyunsaturated fatty acids are essential, so they must be provided through the diet, as their biological synthesis is limited, making it essential to meet their requirements during physiological stages such as pregnancy and lactation. A narrative review was conducted on the effects of omega-3 supplementation during pregnancy and lactation on the fatty acid composition of breast milk in the first months of life. Eight randomized clinical studies were analyzed, showing a significant increase in docosahexaenoic acid (DHA) concentration in breast milk (BM) post-supplementation, compared to control groups. One study evaluated the dose needed to achieve 8 % DHA in erythrocytes and 1 % DHA in BM, reaching these levels with a supplementation close to 1 g of docosahexaenoic acid + eicosapentaenoic acid (EPA). Finally, a trial was found that used supplementation with small lipid contributions (0,59 g α-linolenic acid (ALA)), without generating significant changes in the DHA composition of LM, but in the ALA content. Therefore, it is inferred that omega-3 supplementation beneficially modifies DHA and EPA levels in the composition of BM in pregnant women and during the lactation stage, although further studies are needed to identify doses, times, beneficial effects on development, and more efficient forms of delivery of omega-3 supplementation.

Exposure to environmental neurotoxic substances and neurodevelopment in children from Latin America and the Caribbean

Environmental (and occupational) exposure to neurotoxic substances is a worldwide problem that can affect children's neurodevelopment (ND). In Latin American and Caribbean (LAC) countries there are over 300 million children living under the threat of neurodevelopmental delays due to toxic environmental exposure. Large industrial centers, intense mining and agricultural activities, along with changing complex ecosystems constitute a mosaic that drives contamination of air, water and the food chain. Neurotoxic contaminants such as pesticides (organochlorines, organophosphates, carbamates, pyrethroids, neonicotinoids, and manganese fungicides), chemicals of industrial use (phthalates), and metals (Hg, Pb, Al, As, F, Cd, Mo, Mn) are at the center of environmental exposure studies. Exposure to neurotoxic substances singly or in combination with other compounds or socioeconomic stressors (maternal education, socio-economic and nutritional status) intertwined with occupational and para-occupational exposure can affect ND (motor, cognition, behavior) of children. Significant negative effects of pesticides and neurotoxic elements on ND were found in all studied countries, affecting especially the less-privileged children from laboring families. Studies showed that exposures to the neurotoxicants in human milk are secondary to their more lasting effects during prenatal exposure. This review integrates exposure (prenatal and breastfeeding), metabolism, and ND effects of neurotoxicants. It highlights the overwhelming evidence showing that current levels of exposures are hazardous and detrimental to children's ND in LAC countries. The evidence indicates that a reduction in neurotoxicant exposure is essential to protect children's ND. Therefore, it is urgent to adopt policies and actions that prevent and remediate region-specific children's ND issues.

Maternal Health and Nutrition Status, Human Milk Composition, and Growth and Development of Infants and Children: A Prospective Japanese Human Milk Study Protocol

It is unknown whether maternal health and nutrition are related to human milk composition or growth and development of infants and children. Here, we describe a protocol for a prospective five-year cohort study to clarify (i) how maternal health and nutrition, socioeconomic factors, and lifestyles affect human milk composition, and (ii) whether these are associated with growth and development of infants and children. In our study, we recruited 1210 Japanese mothers with singleton pregnancies from 73 obstetrics clinics and hospitals across Japan, between 2014 and 2019. We will measure the following: health information regarding maternal-child dyads using a self-administered questionnaire, maternal nutrition during breastfeeding using a Brief self-administrated Diet History Questionnaire, the development of infants and children using the Kinder Infant Development Scale, and the stress related to child rearing using the Mother’s Child Care Stress Scale. Simultaneously, we will collect human milk every 2 months during the first year after birth to measure its composition and levels of macronutrients. This study will generate useful data to investigate whether health status, nutritional status, lifestyle, and socioeconomic factors affect human milk composition and the growth and development of infants and children.