All Babies

A common thread in professional social media posts and elsewhere is in regard to the difficulties that infants often display in learning or relearning how to breastfeed following a learning experience with an artificial nipple, particularly but not only during early learning.

Such infant feeding difficulties are addressed in the guidance offered in Step 9 of the Ten Steps to Successful Breastfeeding, which advises, "Counsel mothers on the use and risks of feeding bottles, teats and pacifiers." These common infant breastfeeding challenges include difficulty with the oral grasp and/or disorganized sucking, and are reflected in three important precepts from the cognitive sciences:

1) Early memories are fragile, including motor memories. Consider the challenges of learning a new computer password, as well as the challenges in learning how to perform a new piece of music or a new sports skill. When parents are teaching their teen how to drive a vehicle with a standard transmission, the initial practice on the standard vehicle will not be immediately followed by a week or month of practice driving a vehicle with an automatic transmission — not if the goal is learning how to drive the vehicle with a standard transmission.

2) Task switching is cognitively demanding across the lifespan. It's challenging to discern and differentiate between things that are similar yet different, such as differentiating one identical twin from the other, or discerning one type of red wine from another.

3) The younger we are, the greater the cognitive demands in task switching. Task switching has been heavily studied in the cognitive sciences, with 6,835 search results in PubMed today using the term “task switching”.

The language in Step 9 infers that infants need to be given frequent and consistent practice opportunities that are specific to the task. The Specificity Principle, also termed learning specificity or practice specificity, informs us that in order for learning to be effective, practice must be specific to the task. We can expect our performance to improve over time when we have the opportunity for such practice.

In infancy, even with the support of the primitive survival reflexes, we need enough repetition of task-specific practice over time in order to gradually build robust motor memory for the oral grasp and effective suckling toward the adequate transfer of milk. In other words, the presence of the primitive survival reflexes does not guarantee the oral grasp and effective suckling for all infant milk-feeding methods all the time.

Note that parents of exclusively bottle-feeding infants are NOT taught to alternate styles of bottle nipples from one feeding to the next, from one day to the next, or from week to the next. Bottle-feeding parents often discuss which brand of artificial nipple their baby will accept, and thus the challenges in task-switching for infant milk-feeding skills reflect the cognitive demands for task-switching in all babies all the time.

When a hospitalized bottle-feeding infant first begins oral feedings, particularly in NICU (neonatal intensive care unit) settings as well as in all hospital settings, information is always shared between colleagues and with family members in regard to how well the baby is bottle-feeding. During the change of shift, the departing nurse gives a report on her patients to the incoming nurse, and for bottle-feeding patients who have initiated oral feeds, the incoming nurse is informed about the type of artificial nipple each bottle-feeding patient is currently using, as in “Baby Smith has been doing well today with the Brand A nipple”. The incoming nurse intuitively and implicitly understands this report to mean that Brand A style of artificial nipple will continue to be used in bottle-feeding Baby Smith on the upcoming shift, unless a change in the baby’s feeding performance or health status necessitates a change in feeding method. We do not expect to ever read a medical order in a bottle-feeding baby's chart to alternate the style of artificial nipple from one feed to the next, one shift to the next, one day to the next, or from one week to the next.

Similarly, when the 6-month-old infant begins to learn how to use a sippee-cup, parents do not expect their baby to readily switch back and forth between different styles of sippee-cups.

The toddler who is learning how to use a spoon and fork often confuses the correct movements for using the spoon and fork (Utensil Confusion Part 1). For those of us who have invested much utensil-learning time in first learning how to use a spoon and fork correctly, we might later accept an opportunity to learn how to use chopsticks. Even though the trajectory from plate to mouth is identical when using a spoon, fork, and chopsticks, the manual grasp of each of these implements is very different, and Utensil Confusion Part 2 will ensue.

IBCLCs and other infant feeding specialists are often asked to assist dyads in the infant’s transfer of learning from bottle-feeding skills to the learning of breastfeeding skills (motor learning toward motor control for the oral grasp as well as effective suckling). Skin-to-skin contact is a first recommendation in helping infants with this transfer of learning, providing a rich sensory milieu for the infant in regard to smell, touch, taste, and hearing, but also in regard to the infant’s critical need to become familiar with the visual field at the breast and the necessary movement toward the breast, which is in stark contrast to the movement of a pacifier or bottle toward the infant.

Following the infant’s learning experience(s) with pacifiers and/or bottle-feeding, parents as well as clinicians frequently observe the subsequent inhibition of the infant’s reflexive movements toward the breast. Response inhibition is also heavily studied in the cognitive sciences, and we see this inhibition from birth when breastfeeding infants are given a learning experience with an artificial nipple and subsequently display skill decay when returning to the breast. Skill decay is reflected in the infant’s decreased speed and decreased accuracy for the oral grasp and/or effective suckling at the breast, and this can be measured as the inhibition of return (IOR) — the delay in responding to the previously cueing stimuli. Today’s PubMed search using the term “response inhibition” yielded 408,993 results.

In the hoped-for transfer of learning for the infant from bottle-feeding skills and/or pacifier use to the acquisition of breastfeeding skills, nipple shields are frequently provided to the baby at the breast, utilizing the sensory similarities of nipple shields (nipple shields are more similar to artificial nipples as compared to the sensory milieu of the nipple-areolar complex).

Finger-feeding is often very helpful in assisting infants with the transfer of learning from bottle feeding to the breast, particularly during early learning. Nipple shields can often be avoided entirely when employing finger-feeding in such instances.

Finger-feeding is also helpful in assisting infants with a transfer of learning from the use of a nipple shield at the breast to learning the oral grasp at the breast without the support of a nipple shield.

Transfer of learning is one of many formal terms from the field of kinesiology -- the study of human movement, motor learning, and motor control.

From Germany, two recent studies among many on response inhibition:

Title: Alpha and Theta Bands Dynamics Serve Distinct Functions during Perception-Action Integration in Response Inhibition.

In: Journal of Cognitive Neuroscience 2022 May 2;34(6):1053-1069. doi: 10.1162/jocn_a_01844.

Authors: Astrid Prochnow, Elena Eggert, Alexander Münchau, Moritz Mückschel, Christian Beste.

Abstract only: https://direct.mit.edu/jocn/article-abstract/34/6/1053/109891/Alpha-and-Theta-Bands-Dynamics-Serve-Distinct

Title: Pretrial Theta Band Activity Affects Context-dependent Modulation of Response Inhibition.

In: Journal of Cognitive Neuroscience 2022 March 5;34(4):605-617.

Authors: Paul Wendiggensen, Filippo Ghin, Anna Helin Koyun, Ann-Kathrin Stock, Christian Beste.

Abstract only: https://direct.mit.edu/jocn/article-abstract/34/4/605/109210/Pretrial-Theta-Band-Activity-Affects-Context?redirectedFrom=fulltext

New Studies

The first two of the following 3 open-access studies examined breastfeeding duration. In the first study from Brazil, predictors of interruption of exclusive breastfeeding were the mothers' return to work or study shortly after the baby's birth and the use of a pacifier. The association of shorter duration of exclusive breastfeeding with the early return to paid work outside the home underscores the most basic and profound need for adequate paid maternity leave following an infant’s birth. In addition, the cognitive demands of task switching are also well-known -- of discerning and differentiating between things that are similar yet different re: switching back and forth between the breast and an artificial nipple. The cognitive demands of task switching have been and continue to be heavily studied in the cognitive sciences.

The second study comes from Germany, where researchers found that a high breastfeeding promotion index (BPI) via the World Health Organization's "Ten Steps to Successful Breastfeeding" was associated with higher odds of exclusive breastfeeding during the hospital stay and at discharge, while maternal factors for exclusive breastfeeding (breastfeeding experience and no early use of a pacifier) persisted beyond the hospital stay and date of discharge.

The third study below is from Iran, which compared the effects of two methods of sucking (on pacifier and mother's finger prior to gavage) on oral feeding behavior in preterm babies. Shortest hospitalizations in this preterm population were associated with sucking on the mother's finger.

Title: Determinants of the interruption of exclusive breastfeeding at the 30th day after birth.

In: Revista Paulista de Pediatria 2022; 40: e2021096.

Authors: Daniele Azevedo Kanan de Freitas, Thaymê Pires, Bruna dos Santos Willges, Letícia Daudt, Kimberli Dantas Käfer, Franciele da Silva Martins, Leandro Meirelles Nunes.

Abstract: "Objective: To estimate the prevalence of exclusive breastfeeding (EBF), introduction of water, herbal teas, or other milks, as well as to identify the factors associated with the interruption of EBF at the 30th day after birth. Methods: This is a cross-sectional study using structured and pretested questionnaires applied to 310 mothers in two moments: in person, at the maternity ward; and at the time the infant was 30 days of age, by telephone call. Descriptive statistics and multivariate Poisson regression, following a multilevel hierarchical model according to the proximity to the outcome, were used to estimate the association between dependent and independent variables. Results: The maintenance of EBF at 30 days of age of the infant occurred in 85.2% of the sample, 1.6% receiving water, 11.5% herbal teas, and 8.2% other milk. Predictors for EBF interruption in the univariate analysis were the mothers' return to work or study activities shortly after the baby's birth (IR 2.88; 95%CI 1.14-7.25) and the use of a pacifier (IR 3.29; 95%CI 1.52-6.22). The interruption of EBF was lower in the group of participants who received support from the infant's maternal grandmother (IR 2.71; 95%CI 1.11-6.56) and their partner (IR 4.78; 95%CI 1.90-12.06). After a multivariate analysis, only the use of a pacifier (IR 5.47; 95%CI 2.38-19.3) and the partner's support (IR 6.87; 95%CI 2.04-23.1) maintained the association with the outcome.

Conclusions: The prevalence of EBF found in this study can be considered good, and future interventions aimed at increasing the duration of EBF in this population should take into account the participation of the partner and the reinforcement for not introducing the pacifier."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9190477/

Title: The role of breastfeeding promotion in German hospitals for exclusive breastfeeding duration.

In: Maternal & Child Nutrition 2022 Apr; 18(2): e13326.

Authors: Nele Hockamp, Erika Sievers, Philipp Hülk, Henrik Rudolf, Silvia Rudloff, Thomas Lücke, and Mathilde Kersting.

Abstract: "Breastfeeding promotion and support in hospitals is expected to have a positive impact on maternal breastfeeding outcomes. The objective of this study is to examine the association between breastfeeding promotion in maternity hospitals in Germany and exclusive breastfeeding (EBF) rates during the first 4 months. Thus, a nationwide cross‐sectional web‐based survey of breastfeeding promotion was conducted in 103 hospitals. Mother–infant pairs (n = 962) were recruited at these hospitals for a prospective web‐based survey of breastfeeding status at five‐time points, that is, during a hospital stay, at discharge as well as after 0.5, 2, and 4 months. The hospital analysis was based on the “10 Steps to Successful Breastfeeding” of the World Health Organization and the United Nations Children's Fund, adapted for Germany. Their degree of implementation was stratified by a breastfeeding promotion index (BPI) as low (≤5 steps), medium (6–8 steps), and high (≥9 steps). The association between the BPI and the odds of EBF at each of the five‐time points was estimated by multivariable regression models, adjusting for various maternal factors. At all time points, the proportion of EBF among mothers from high BPI hospitals exceeded the proportion of those from medium or low BPI hospitals. A high BPI was associated with higher odds of EBF during the hospital stay and at discharge, while maternal factors for EBF such as breastfeeding experience and no early use of a pacifier persisted beyond. The high commitment of hospitals and tailored support of mothers is essential for EBF."

Keywords: breastfeeding determinants, breastfeeding duration, breastfeeding promotion, exclusive breastfeeding, maternity hospitals, WHO/UNICEF ten steps

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8932702/

From Iran:

Title: Comparison of the effect of two methods of sucking on pacifier and mother's finger on oral feeding behavior in preterm infants: a randomized clinical trial.

In: BMC 2022 May 18;22(1):292.

Authors: Fatemeh Shaki, Parvin Aziznejadroshan, Zahra Akbarian Rad, Mohammad Chehrazi, Afsaneh Arzani.

Abstract: "Background: Oral feeding problems will cause long-term hospitalization of the infant and increase the cost of hospitalization. This study aimed to compare the effect of two methods of sucking on pacifier and mother's finger on oral feeding behavior in preterm infants. Methods: This single-blind randomized controlled clinical trial was performed in the neonatal intensive care unit of Babol Rouhani Hospital, Iran. 150 preterm infants with the gestational age of 31 to 33 weeks were selected and were divided into three groups of 50 samples using randomized block method, including non-nutritive sucking on mother's finger (A), pacifier (B) and control (C). Infants in groups A and B were stimulated with mother's finger or pacifier three times a day for five minutes before gavage, for ten days exactly. For data collection, demographic characteristics questionnaire and preterm infant breastfeeding behavior scale were used. Results: The mean score of breastfeeding behavior in preterm infants in the three groups of A,B,C was 12.34 ± 3.37, 11.00 ± 3.55, 10.40 ± 4.29 respectively, which had a significant difference between the three groups (p = 0.03). The mean rooting score between three groups of A, B, and C was 1.76 ± 0.47, 1.64 ± 0.48, and 1.40 ± 0.90 (p < 0.001) respectively. Also, the mean sucking score in groups of A, B and C was 2.52 ± 0.76, 2.28 ± 0.64 and 2.02 ± 0.74 respectively, which had a significant difference (p = 0.003), but other scales had no significant difference between the three groups (P > 0.05). The mean time to achieve independent oral feeding between the three groups of A, B, C was 22.12 ± 8.15, 22.54 ± 7.54 and 25.86 ± 7.93 days respectively (p = 0.03), and duration of hospitalization was 25.98 ± 6.78, 27.28 ± 6.20, and 29.36 ± 5.97 days (p = 0.02), which had a significant difference. But there was no significant difference between the two groups of A and B in terms of rooting, sucking, the total score of breastfeeding behavior and time of achieving independent oral feeding (P > 0.05). Conclusion: Considering the positive effect of these two methods, especially non-nutritive sucking on mother's finger, on increasing oral feeding behaviors, it is recommended to implement these low-cost methods for preterm infants admitted to neonatal intensive care unit."

https://bmcpediatr.biomedcentral.com/articles/10.1186/s12887-022-03352-9

A New Study and Three Review Articles

Some new papers, beginning with this study from the University of Amsterdam in The Netherlands:

Title: Human milk inhibits some enveloped virus infections, including SARS-CoV-2, in an intestinal model.

In: Life Science Alliance 2022 Dec; 5(12): e202201432.

Authors: Ikrame Aknouch, Adithya Sridhar, Eline Freeze, Francesca Paola Giugliano, Britt J van Keulen, Michelle Romijn, Carlemi Calitz, Inés García-Rodríguez, Lance Mulder, Manon E Wildenberg, Vanesa Muncan, Marit J van Gils, Johannes B van Goudoever, Koert J Stittelaar, Katja C Wolthers, and Dasja Pajkrt.

Abstract: "Human milk is important for antimicrobial defense in infants and has well demonstrated antiviral activity. We evaluated the protective ability of human milk against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a human fetal intestinal cell culture model. We found that, in this model, human milk blocks SARS-CoV-2 replication, irrespective of the presence of SARS-CoV-2 spike-specific antibodies. Complete inhibition of both enveloped Middle East respiratory syndrome coronavirus and human respiratory syncytial virus infections was also observed, whereas no inhibition of non-enveloped enterovirus A71 infection was seen. Transcriptome analysis after 24 h of the intestinal monolayers treated with human milk showed large transcriptomic changes from human milk treatment, and subsequent analysis suggested that ATP1A1 down-regulation by milk might be of importance. Inhibition of ATP1A1 blocked SARS-CoV-2 infection in our intestinal model, whereas no effect on EV-A71 infection was seen. Our data indicate that human milk has potent antiviral activity against particular (enveloped) viruses by potentially blocking the ATP1A1-mediated endocytic process."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9354649/

Title: Preterm birth and human milk proteome: are we ready for individualized fortification?

In: Current Opinion in Clinical Nutrition and Metabolic Care 2022 May 1;25(3):216-222. doi: 10.1097/MCO.0000000000000824.

Authors: Jing Zhu, Mengyuan Liu, Yan Xing.

Abstract "Purpose of review: Preterm birth is one of the most pressing clinical problems in obstetrics and neonatology worldwide. One of the most sophisticated components of human milk is the proteome and a better understanding of it can lead to precision guides for feeding preterm infants. In this review, we will examine recent research focused on the human milk proteome and individualized protein fortification of human milk. Recent findings: In both preterm and term birth, the protein content in mother's own milk dropped rapidly in the early postnatal period. Preterm milk had a higher protein content and contained different protein and endogenous peptide compositions compared with term milk. The peptides in gastrointestinal fluids of preterm infants still need further investigation. Individualized fortification is more superior to standard fortification, but it only focuses on the total protein amount. There is no data concerning the composition and posttranslational modifications of proteins and endogenous peptides with fortification and their longterm effects. Summary: Comprehensive identification and characterization of the human milk proteome have led to the targeted breast milk fortification theory of preterm infant feeding and has also been enriched by clinical trials. However, to achieve fortification of key proteins and/or endogenous peptides, as standard clinical practice, requires additional studies. Future research should explore the long-term effect of protein fortification and pay more attention to quality rather than quantity in relation to infant body composition and growth outcomes."

Open access: https://journals.lww.com/co-clinicalnutrition/Fulltext/2022/05000/Preterm_birth_and_human_milk_proteome__are_we.15.aspx

Title: Human Milk Extracellular Vesicles: A Biological System with Clinical Implications.

In: Cells 2022 Jul 30;11(15):2345. doi: 10.3390/cells11152345.

Authors: Somchai Chutipongtanate, Ardythe L Morrow, David S Newburg.

Abstract: "The consumption of human milk by a breastfeeding infant is associated with positive health outcomes, including lower risk of diarrheal disease, respiratory disease, otitis media, and in later life, less risk of chronic disease. These benefits may be mediated by antibodies, glycoproteins, glycolipids, oligosaccharides, and leukocytes. More recently, human milk extracellular vesicles (hMEVs) have been identified. HMEVs contain functional cargos, i.e., miRNAs and proteins, that may transmit information from the mother to promote infant growth and development. Maternal health conditions can influence hMEV composition. This review summarizes hMEV biogenesis and functional contents, reviews the functional evidence of hMEVs in the maternal-infant health relationship, and discusses challenges and opportunities in hMEV research. Keywords: breastmilk; exosomes; extracellular vesicles; human milk; maternal–child health outcomes; non-coding RNAs."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9367292/

Title: Human Milk and Preterm Infant Brain Development: A Narrative Review.

In: Clinical Therapeutics 2022 Apr;44(4):612-621. doi: 10.1016/j.clinthera.2022.02.011.

Authors: Mandy Brown Belfort, Terrie E Inder.

Abstract: "Purpose: To review and synthesize the literature on human milk and structural brain development and injury in preterm infants, focusing on the application of quantitative brain magnetic resonance imaging (MRI) in this field. Methods: For this narrative review, we searched PubMed for articles published from 1990 to 2021 that reported observational or interventional studies of maternal milk or donor milk in relation to brain development and/or injury in preterm infants assessed with quantitative MRI at term equivalent age. Studies were characterized with respect to key aspects of study design, milk exposure definition, and MRI outcomes. Findings: We identified 7 relevant studies, all of which were observational in design and published between 2013 and 2021. Included preterm infants were born at or below 33 weeks' gestation. Sample sizes ranged from 22 to 377 infants. Exposure to human milk included both maternal and donor milk. No study included a full-term comparison group. Main MRI outcome domains were white matter integrity (assessed with diffusion tensor imaging, resting state functional connectivity, or semiautomated segmentation of white matter abnormality) and total and regional brain volumes. Studies revealed that greater exposure to human milk versus formula was associated with favorable outcomes, including more mature and connected cerebral white matter with less injury and larger regional brain volumes, notably in the deep nuclear gray matter, amygdala-hippocampus, and cerebellum. No consistent signature effect of human milk exposure was found; instead, the beneficial associations were regional and tissue-specific neuroprotective effects on the areas of known vulnerability in the preterm infant. Implications: Evidence to date suggests that human milk may protect the preterm infant from the white matter injury and dysmaturation to which this population is vulnerable. Brain MRI at term equivalent age is emerging as a useful tool to investigate the effects of human milk on the preterm brain. When grounded in neurobiological knowledge about preterm brain injury and development, this approach holds promise for allowing further insight into the mechanisms and pathways underlying beneficial associations of human milk with neurodevelopmental outcomes in this population and in the investigation of specific milk bioactive components with neuroprotective or neurorestorative potential. Keywords: brain development; dysmaturation; human milk; preterm infants; white matter injury."

Abstract only: https://www.clinicaltherapeutics.com/article/S0149-2918(22)00081-9/fulltext

A New Study on Breastfeeding Duration and Vagal Regulation in Nursing Dyads

Those of us who have been in the field for decades may recall a particularly well-known photograph of two mothers sitting side-by-side, feeding their infants. In the dyad on the left of the photo, the mother is bottle-feeding her baby. In the dyad on the right, the baby is being fed at the breast. There are distinct differences in the two dyads: the bottle-feeding baby is not held close to the mother's body, and the bottle-feeding mother is frowning at the nursing mother next to her, who is holding her baby close and actively engaging with her baby, smiling and appearing to be talking to her infant as he nurses.

The following new study from China immediately brought to mind the above-mentioned photograph from decades ago. I have long been interested in Tronick's Still-Face Paradigm, and this new study is one of many that have utilized Tronick's Still-Face Paradigm over recent decades. Edward Tronick is a Distinguished University Professor of Psychology at the University of Massachusetts at Boston and is well-known for his body of work, including the development of his Still-Face Paradigm in the 1970s. Over the course of his career, Tronick has focused on the neurobehavioral and social-emotional development of infants and young children, parenting in the U.S. and other cultures, and infant-parent mental health.

The new study:

Title: Breastfeeding duration and vagal regulation of infants and mothers.

In: Early Human Development 2022 Aug;171:105620.

Authors: Qili Lan, Hongxia Li, Li Wang, Suying Chang.

doi: 10.1016/j.earlhumdev.2022.105620. Epub 2022 Jun 28.

Highlights:

- Vagal regulation, indexed by RSA (respiratory sinus arrhythmia, a component of heart rate variability), supports self-regulation and social engagement.

- Longer breastfeeding duration is associated with lower infant RSA throughout the still-face paradigm.

- Longer breastfeeding duration is associated with higher overall RSA levels in mothers throughout the still-face paradigm.

- Greater breastfeeding duration contributes to infant adaptive vagal regulation during an interaction.

Abstract: "Background: Vagal regulation within the parasympathetic nervous system supports self-regulation and social engagement. Research has suggested that early feeding practices may influence mother-infant vagal functioning. Aim: We aimed to examine the association between breastfeeding duration and mother-infant vagal regulation during an interaction. We hypothesized that breastfeeding duration would be positively associated with adaptive vagal regulation in infants and mothers. Method: 204 mother-infant dyads (infant mean age 6 months) completed the face-to-face still-face (FFSF) task. During the task, vagal regulation indexed by respiratory sinus arrhythmia (RSA, a component of heart rate variability) was calculated through continuously recorded electrocardiogram signals. Breastfeeding duration and demographic information were reported by mothers. Linear mixed models were adopted to estimate the associations between breastfeeding duration and repeated measures of RSA in infants and mothers throughout the FFSF. Results: Infants breastfed for a longer duration demonstrated lower RSA throughout the FFSF (B = −0.06, 95 % CI: −0.09 to −0.03), suggesting active physiological mobilization to engage in interaction and regulate distress. Mothers with longer breastfeeding duration displayed higher baseline RSA and higher overall RSA levels (higher vagal control) during the FFSF (B = 0.06, 95 % CI: 0.02 to 0.09), indicating a calmer and regulated state. Conclusion: Longer breastfeeding duration was associated with more adaptive mother-infant vagal regulation during the interaction, indicating a positive dose-response association. This finding reveals breastfeeding practice as a factor contributing to infant effective vagal regulation and further supports WHO recommendation on exclusive breastfeeding for the first 6 months and continuing breastfeeding to 24 months and beyond."

Abstract only: https://www.sciencedirect.com/science/article/abs/pii/S0378378222000834?via%3Dihub

Tronick's professional bio refers to his work in NICU populations and much more: https://www.umb.edu/academics/cla/faculty/edward_tronick

There are many published interviews in print and on video with Tronick discussing the Still-Face Paradigm and other aspects of mental health in parents and children. Here are a few:

https://www.psychhelp.com.au/what-does-the-still-face-experiment-teach-us-about-connection/

"Trusting Relationships Are Central to Children's Learning -- Lessons From Edward Tronick". Tronick discusses his goal to pursue how relationships affect children's development: "I [wanted] to understand what's going on in the exchange [between a parent and child] that allows a relationship to be 'good' or 'smooth.' What do these words mean? Can we describe them, and can we come to an understanding of that process?" https://www.huffpost.com/entry/trusting-relationships-ar_b_1123524

"Effects of Child Abuse Can Last a Lifetime: Watch the ‘Still Face’ Experiment to See Why" https://www.washingtonpost.com/blogs/she-the-people/wp/2013/09/16/affects-of-child-abuse-can-last-a-lifetime-watch-the-still-face-experiment-to-see-why/

Tronick's most recent book (2020), co-authored with Claudia M. Gold, M.D., is The Power of Discord: Why the Ups and Downs of Relationships Are the Secret to Building Intimacy, Resilience, and Trust. His 2007 book, The Neurobehavioral and Social Emotional Development of Infants and Children, is considered a tour de force according to a review in New England Psychologist.

Today's PubMed search using "still-face paradigm" yielded 439 results. https://pubmed.ncbi.nlm.nih.gov/?term=still+face+paradigm

A PubMed search using "Edward Tronick" yielded these results: https://pubmed.ncbi.nlm.nih.gov/?term=edward+tronick

New Study from The Netherlands on Brief to Absent Breastfeeding in a 19th Century Rural Dutch Farming Community

In this interesting new study, anthropologists examined infant bones from a 19th-century rural Dutch dairy farming community, finding little to no evidence of breastfeeding:

Title: Isotopic reconstruction of short to absent breastfeeding in a 19th century rural Dutch community.

In: PLOS One April 13, 2022. https://doi.org/10.1371/journal.pone.0265821

Authors: Andrea L. Waters-Rist, Kees de Groot, Menno L. P. Hoogland.

Abstract: "Artificial feeding of young infants is considered a modern phenomenon. However, historical sources note its practice in some past European populations. This research explores factors that contributed to a short to absent period of breastfeeding in pre-modern Netherlands. Stable nitrogen and carbon isotope analysis is undertaken on 277 19th century individuals from Beemster, a, rural, mainly Protestant, dairy farming community. An intra-individual sampling approach for ≤6 year-olds compares newer metaphyseal to older diaphyseal long bone collagen to classify feeding status at death. Archivally identified individuals permit analyses of sex and year-of-death. Few infants have isotopic evidence for breastfeeding and, if present, it was likely of short duration or a minor source of dietary protein. From only a few weeks to months of age infants were fed cow’s milk and paps with sugar. There is broad dietary homogeneity with no sex or temporal isotopic differences, but young infants (1–11 months) have the most ẟ15N and ẟ13C variation highlighting the effect of multiple dietary and physiological processes. Beemster had many factors associated with high rates of breastfeeding in other Dutch communities, yet most mothers did not breastfeed, or not for long, showing that regional variation in infant feeding is influenced by community values and traditions. On top of child rearing and domestic chores, female dairy farmers were in charge of milking cattle and dairy production, an important income source, suggesting high workload was also a factor in short or absent breastfeeding periods, aided by the constant supply of fresh milk that could be fed to an infant by an older sibling."

Open access: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0265821

News release from Western University includes comments from senior author Angela L. Waters-Rist, an anthropology professor and expert in human osteoarchaeology: https://news.westernu.ca/2022/04/busy-mothers-breastfeeding/

Some New Studies and a Review

Title: Associations between exclusive breastfeeding duration and children's developmental outcomes: Evidence from Siaya county, Kenya.

In: PLoS One. 2022; 17(3): e0265366. Published online 2022 Mar 31.

doi: 10.1371/journal.pone.0265366

Authors: Silas Onyango, Elizabeth Kimani-Murage, Patricia Kitsao-Wekulo, Nelson K. Langat, Kenneth Okelo, Christopher Obong’o, Jürg Utzinger, Günther Fink.

Abstract: "Background: Exclusive breastfeeding (EBF) during the first 6 months of life is widely promoted as a key strategy to enhance child health, growth, and development. Even though a high proportion of children in Kenya are currently breastfed exclusively, there is little evidence regarding the developmental benefits during the first year of life. This paper aims to fill this gap by establishing an association between EBF and early childhood developmental outcomes among children below the age of 6 months in Kenya. Methods: We used data collected as part of a cluster-randomized controlled trial conducted in Bondo sub-county in the western part of Kenya to assess the associations between EBF and development in the first year of life. The primary exposure variable was EBF, and the outcome variable was child development as measured by the Ages and Stages Questionnaire-Third Edition (ASQ-3). Results: We analyzed data from 570 children aged below 6 months at the time of the interview. Breastfeeding children exclusively between 3 and 6 months was associated with 0.61 standard deviation (SD) higher ASQ-3 scores in the adjusted model. When specific domains were considered, in the adjusted models, EBF in the 3-6 months period was associated with 0.44 SD, 0.34 SD, and 0.36 SD higher ASQ-3 scores in communication, gross motor, and problem solving domains, respectively. There were weak associations in the fine motor and social-emotional domains. Conclusion: EBF in the 3- to 6-month age range has significant positive associations with child development, especially for communication, gross motor, and problem-solving. Programs encouraging mothers to continue EBF in this period may have substantial benefits for children."

Open access: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0265366

Title: Hormones regulating energy homeostasis in breastfeeding versus formula feeding mothers.

In: Journal of Physiology and Pharmacology 2021 Oct;72(5):731-739.

doi: 10.26402/jpp.2021.5.08. Epub 2022 Feb 12.

Authors: J Nurek, O W Wisniewski, J Kupsz, H Krauss, Z Buchwald, Z Checinska-Maciejewska, M Gibas-Dorna.

Abstract: "To meet energy demands for lactogenesis and to sustain homeostatic conditions post-partum, the organism of breastfeeding mother undergoes combined endocrine and metabolic regulation. The main objective of this study was to determine basal serum concentrations of hormones involved in the maintenance and defense of energy balance in breastfeeding (BF) and formula feeding (FF) mothers. Twenty healthy exclusively breastfeeding mothers at 3rd month of lactation (EBF3), 17 healthy partially breastfeeding at 6th month of lactation (PB6) and 17 healthy FF mothers participated in this study. Fasting serum prolactin (PRL), acylated ghrelin (aGhr), total ghrelin (tGhr), leptin, adiponectin, insulin, and cortisol were determined for all study participants and correlations between studied parameters were calculated for BF women. We found significantly lower basal insulin (p = 0.0048) and cortisol (p = 0.0002) and significantly elevated basal prolactin (p = 0.0020) and leptin (p = 0.0416) in BF when compared with FF women. The differences were not associated with the duration of lactation (3 vs. 6 months), except for PRL, which was highest in EBF3. Levels of Ghr and adiponectin did not differ between study groups. In the BF group, the negative correlations were found between aGhr and insulin, aGhr and adiponectin, leptin and cortisol, leptin and adiponectin, insulin and adiponectin, cortisol and adiponectin. Positive associations were noted between: insulin and leptin, leptin and aGhr, PRL and leptin, PRL and aGhr. Leptin and insulin correlated positively, whereas adiponectin negatively with BMI. These data may suggest that EBF3 and PB6 as compared with FF mothers, exhibit hormonal regulation which tends to be more advantageous for their metabolic profile and is not related to the duration of breastfeeding within the first 6 months of lactation."

Open access: https://www.jpp.krakow.pl/journal/archive/10_21/pdf/10.26402/jpp.2021.5.08.pdf

Title: Kangaroo mother care had a protective effect on the volume of brain structures in young adults born preterm.

In: Acta Paediatrica 2022 May;111(5):1004-1014.

Authors: Nathalie Charpak, Rejean Tessier, Juan Gabriel Ruiz, Felipe Uriza, José Tiberio Hernandez, Darwin Cortes, Adriana Montealegre-Pomar.

Abstract: "Aim: The protective effects of Kangaroo mother care (KMC) on the neurodevelopment of preterm infants are well established, but we do not know whether the benefits persist beyond infancy. Our aim was to determine whether providing KMC in infancy affected brain volumes in young adulthood. Method: Standardised cognitive, memory, and motor skills tests were used to determine the brain volumes of 20-year-old adults who had formed part of a randomized controlled trial of KMC versus incubator care. Multivariate analysis of brain volumes was conducted according to KMC exposure. Results: The study comprised 178 adults born preterm: 97 had received KMC and 81 were incubator care controls. Bivariate analysis showed larger volumes of total grey matter, basal nuclei and cerebellum in those who had received KMC, and the white matter was better organised. This means that the volumes of the main brain structures associated with intelligence, attention, memory and coordination were larger in the KMC group. Multivariate linear regression analysis demonstrated the direct relationship between brain volumes and duration of KMC, after controlling for potential confounders. Conclusion: Our findings suggest that the neuroprotective effects of KMC for preterm infants persisted beyond childhood and improved their lifetime functionality and quality of life. Keywords: Kangaroo mother care; grey matter; magnetic resonance imaging; premature infants; white matter."

Open access: https://onlinelibrary.wiley.com/doi/epdf/10.1111/apa.16265

Title: Increasing the exclusive breastfeeding rate in a private hospital in UAE through quality improvement initiatives.

In: Journal of Neonatal-Perinatal Medicine 2022;15(1):179-186. doi: 10.3233/NPM-210703.

Authors: M Kaushal, K Sasidharan, A Kaushal, P Augustine, M Alex.

Abstract: "BACKGROUND: Mother’s milk is the best, and ideal method for infant feeding. We found that this practice was not being followed in our hospital. A survey was conducted in the unit with regards to breastfeeding practices which revealed that most babies who were discharged from our nursery were on formula supplements. Our goal was to improve established breastfeeding rates in the unit by increasing the number of full-term healthy babies who were discharged on exclusive Breastfeeding. METHOD: A project team was formed, and data were collected through direct observations and direct interviews with postnatal mothers. Exclusive Breastfeeding at discharge was defined as a baby being fully on breastfeed with no additional formula supplements for at least 12 hours prior to discharge. The primary outcome was to increase the percentage of babies being discharged on exclusive Breastfeeding. We used the FOCUS PDCA model to measure improvements and 8 PDCA cycles of 4 weeks duration were implemented to test the changes. RESULTS: The interventions we put in place led to a considerable nine times overall improvement in the established breastfeeding rates. Among all the interventions, the most promising results were observed during the PDCA cycles involving staff education, the introduction of antenatal classes for mothers, skin to skin contact and rooming in. CONCLUSION: Breastfeeding rates in the private sector with nursery services can be improved by reinforcing breastfeeding education for mothers in addition to training the maternal care staff, empowering them to promote and assist in breastfeeding."

Abstract only: https://pubmed.ncbi.nlm.nih.gov/34120921/

A review paper:

Title: Exclusive Breastfeeding and Vitamin D Supplementation: A Positive Synergistic Effect on Prevention of Childhood Infections?

In: International Journal of Environmental Research and Public Health 2022 Mar 3;19(5):2973. doi: 10.3390/ijerph19052973.

Authors: Raffaele Domenici, Francesco Vierucci.

Abstract: "Human milk is the best food for infants. Breastfeeding has been associated with a reduced risk of viral and bacterial infections. Breast milk contains the perfect amount of nutrients needed to promote infant growth, except for vitamin D. Vitamin D is crucial for calcium metabolism and bone health, and it also has extra-skeletal actions, involving innate and adaptive immunity. As exclusive breastfeeding is a risk factor for vitamin D deficiency, infants should be supplemented with vitamin D at least during the first year. The promotion of breastfeeding and vitamin D supplementation represents an important objective of public health. Keywords: COVID-19; breastfeeding; human milk; infections; supplementation; vitamin D."

Open access: https://www.mdpi.com/1660-4601/19/5/2973/htm

New Studies

Title: Association of Breastfeeding Duration with 12-Month Postpartum Blood Lipids in a Predominately Lower-Income Hispanic Pregnancy Cohort in Los Angeles.

In: International Journal of Environmental Research and Public Health 2022 Mar 4;19(5):3008. doi: 10.3390/ijerph19053008.

Authors: Zhongzheng Niu, Christine H Naya, Lorena Reynaga, Claudia M Toledo-Corral, Mark Johnson, Tingyu Yang, Brendan Grubbs, Nathana Lurvey, Deborah Lerner, Genevieve F Dunton, Rima Habre, Carrie V Breton, Theresa M Bastain, Shohreh F Farzan.

Abstract: "Breastfeeding may protect women's long-term cardiovascular health; however, breastfeeding-related postpartum lipid changes remain unclear. We aim to examine associations of breastfeeding duration with maternal lipids at 12 months postpartum. In a subsample (n = 79) of the Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) cohort, breastfeeding status and duration at 3, 6, and 12 months postpartum were self-reported. Serum levels of lipids, including total cholesterol, triglycerides (TG), high-, low-, and very low-density lipoprotein cholesterol (HDL-C, LDL-C, VLDL-C), were measured from blood samples collected at 12 months postpartum. We used linear regression models to compare lipids by breastfeeding duration, adjusting for potential confounders. Women who were breastfeeding at 12 months had higher HDL-C (mean: 41.74 mg/dL, 95% CI: 37.27-46.74 vs. 35.11 mg/dL, 95% CI: 31.42-39.24), lower TG (80.45 mg/dL, 95% CI: 66.20-97.77 vs. 119.11 mg/dL, 95% CI: 98.36-144.25), and lower VLDL-C (16.31 mg/dL, 95% CI: 13.23, 20.12 vs. 23.09 mg/dL, 95% CI: 18.61-28.65) compared to women who breastfed for <6 months. No lipids were significantly different between women who breastfed for 6-11 months and for <6 months. Each month's increase in breastfeeding duration was significantly, inversely associated with TG and VLDL-C and positively with HDL-C. Adjusting for fasting status, demographics, pre-pregnancy body mass index, breastfeeding frequency, and pregnancy complications did not appreciably change effect estimates. Breastfeeding at 12 months postpartum and a longer duration of breastfeeding in the first year postpartum were both associated with increased HDL-C and decreased TG and VLDL-C at 12 months postpartum."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8910591/

Title: Breastfeeding duration is positively associated with decreased smoking relapse in the postpartum period.

In: Midwifery 2022 Feb 21;108:103289. doi: 10.1016/j.midw.2022.103289.

Authors: Kevin Zhang, Linda P Siziba, Nan Ji Suo, Dietrich Rothenbacher, Jon Genuneit.

Abstract: "Introduction: A significant proportion of women quit smoking during pregnancy, creating a unique window of opportunity to encourage long-term smoking cessation. Efforts to prevent smoking relapse in the postpartum period, however, have largely been ineffective. We investigated the association between breastfeeding duration and smoking relapse to help inform postpartum smoking cessation strategies. Methods: The Ulm SPATZ Health Study consists of 1006 newborns and their 970 mothers recruited from April 2012 to May 2013 in Ulm, Germany. For this analysis, only mothers who quit smoking during pregnancy, for whom breastfeeding and smoking data were available, were included. Kaplan-Meier plots were used to investigate the relationship between breastfeeding duration and postpartum smoking relapse within 2 years. Cox proportional hazards regression models were used to estimate hazard ratios, adjusted for factors reported to influence postpartum smoking outcomes. Results: A total of 115 mothers were included. They had a mean age of 32.0 (SD: 5.0) years and breastfed for 5.6 (SD: 4.4) months. Of those who remained in the study, 14 (12.2%) experienced smoking relapse by 6 weeks and 48 (51.1%) relapsed by 2 years. In an adjusted analysis which accounted for age, educational attainment, postpartum weight retention, and gestational weight gain, breastfeeding for at least 6 months was significantly associated with decreased smoking relapse within 2 years (HR: 0.18; 95% CI: 0.07 - 0.45). Conclusions: Breastfeeding for at least 6 months was associated with decreased postpartum smoking relapse. Breastfeeding promotion should be considered to enhance smoking cessation strategies in the postpartum period."

Open access: https://www.sciencedirect.com/science/article/pii/S0266613822000419?via%3Dihub

Title: Short Breastfeeding Duration is Associated With Premature Onset of Female Breast Cancer.

In: Clinical Nursing Research 2022 Jan 25;10547738211069725. doi: 10.1177/10547738211069725.

Authors: Ángel Fernández-Aparicio, Jacqueline Schmidt-RioValle, Pedro A García, Emilio González-Jiménez.

Abstract: "Currently, there is controversy concerning potential factors that contribute to the development of breast cancer. Our study analyzed the possible association between weight status, cigarette consumption, lactation period, serum estrogen levels, family history of breast cancer, and age at breast cancer diagnosis. We conducted a retrospective study at a University Hospital in Granada (Spain) by consulting the medical records of 524 women aged 19 to 91 years, all of them diagnosed and treated for breast cancer from 2011 to 2019. Our findings indicated that in non-morbidly obese females who were also non-smokers, a maternal lactation period of more than 3 months (p = .013) and the absence of family antecedents of cancer (p = .025) were statistically significant factors that led to a more advanced age at breast cancer diagnosis. Thus, maternal lactation seems to have a potential protective effect on breast cancer."

Abstract only: https://journals.sagepub.com/doi/10.1177/10547738211069725?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed

Title: The role of breastfeeding promotion in German hospitals for exclusive breastfeeding duration.

In: Maternal & Child Nutrition 2022 Apr;18(2):e13326. doi: 10.1111/mcn.13326. Epub 2022 Jan 25.

Authors: Nele Hockamp, Erika Sievers, Philipp Hülk, Henrik Rudolf, Silvia Rudloff, Thomas Lücke, Mathilde Kersting.

Abstract: "Breastfeeding promotion and support in hospitals is expected to have a positive impact on maternal breastfeeding outcomes. The objective of this study is to examine the association between breastfeeding promotion in maternity hospitals in Germany and exclusive breastfeeding (EBF) rates during the first 4 months. Thus, a nationwide cross‐sectional web‐based survey of breastfeeding promotion was conducted in 103 hospitals. Mother–infant pairs (n = 962) were recruited at these hospitals for a prospective web‐based survey of breastfeeding status at five‐time points, that is, during a hospital stay, at discharge as well as after 0.5, 2, and 4 months. The hospital analysis was based on the “10 Steps to Successful Breastfeeding” of the World Health Organization and the United Nations Children's Fund, adapted for Germany. Their degree of implementation was stratified by a breastfeeding promotion index (BPI) as low (≤5 steps), medium (6–8 steps), and high (≥9 steps). The association between the BPI and the odds of EBF at each of the five‐time points was estimated by multivariable regression models, adjusting for various maternal factors. At all time points, the proportion of EBF among mothers from high BPI hospitals exceeded the proportion of those from medium or low BPI hospitals. A high BPI was associated with higher odds of EBF during the hospital stay and at discharge, while maternal factors for EBF such as breastfeeding experience and no early use of a pacifier persisted beyond. The high commitment of hospitals and tailored support of mothers is essential for EBF."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8932702/

New Meta-Analysis on Breastfeeding and Reduced Maternal Cardiovascular Risk

Researchers from Austria, the UK, Ireland, the Netherlands, and Australia now have this new open-access meta-analysis in publication:

Title: Breastfeeding Is Associated With a Reduced Maternal Cardiovascular Risk: Systematic Review and Meta‐Analysis Involving Data From 8 Studies and 1,192,700 Parous Women.

In: Journal of the American Heart Association 2022; DOI: 10.1161/JAHA.121.022746

Authors: Lena Tschiderer, Lisa Seekircher, Setor K. Kunutsor, Sanne A. E. Peters, Linda M. O’Keeffe, Peter Willeit.

An excerpt from the ScienceDaily news release:

“The review found that 82% of the women reported they had breastfed at some time in their life. Compared to women who never breastfed, women who reported breastfeeding during their lifetime had a 11% decreased risk of developing cardiovascular disease. Over an average follow-up period of 10 years, women who breastfed at some time in their life were 14% less likely to develop coronary heart disease; 12% less likely to suffer strokes; and 17% less likely to die from cardiovascular disease. Women who breastfed for 12 months or longer during their lifetime appeared to be less likely to develop cardiovascular disease than women who did not breastfeed. There were no notable differences in cardiovascular disease risk among women of different ages or according to the number of pregnancies.

“Despite recommendations to breastfeed by organizations including the WHO and the U.S. Centers for Disease Control and Prevention (CDC), both of which recommend babies are breastfed exclusively through at least six months of age, only 1 in 4 infants receives only breastmilk for the first six months of life. Black infants in the U.S. are less likely than white infants to be breastfed for any length of time, according to the CDC.

“‘It's important for women to be aware of the benefits of breastfeeding for their babies' health and also their own personal health,’ Willeit said. ‘Moreover, these findings from high-quality studies conducted around the world highlight the need to encourage and support breastfeeding, such as breastfeeding-friendly work environments, and breastfeeding education and programs for families before and after giving birth.’

“The U.S. has the highest maternal death rate among developed countries, and cardiovascular disease is the leading cause, according to the 2021 Call to Action Maternal Health and Saving Mothers policy statement from the American Heart Association. The statement, which outlines public policies that address the racial and ethnic disparities in maternal health, notes that an estimated 2 out of 3 deaths during pregnancy may be preventable.”

https://www.sciencedaily.com/releases/2022/01/220111091356.htm?utm_source=feedburner&utm_medium=email

Abstract: "Background: Breastfeeding has been robustly linked to reduced maternal risk of breast cancer, ovarian cancer, and type 2 diabetes. We herein systematically reviewed the published evidence on the association of breastfeeding with maternal risk of cardiovascular disease (CVD) outcomes. Methods and Results: Our systematic search of PubMed and Web of Science of articles published up to April 16, 2021, identified 8 relevant prospective studies involving 1,192,700 parous women (weighted mean age: 51.3 years at study entry, 24.6 years at first birth; weighted mean number of births: 2.3). A total of 982,566 women (82%) reported having ever breastfed (weighted mean lifetime duration of breastfeeding: 15.6 months). During a weighted median follow‐up of 10.3 years, 54,226 CVD, 26,913 coronary heart disease, 30,843 stroke, and 10,766 fatal CVD events were recorded. In a random‐effects meta‐analysis, the pooled multivariable‐adjusted hazard ratios comparing parous women who ever breastfed to those who never breastfed were 0.89 for CVD (95% CI, 0.83–0.95; I2=79.4%), 0.86 for coronary heart disease (95% CI, 0.78–0.95; I2=79.7%), 0.88 for stroke (95% CI, 0.79–0.99; I2=79.6%), and 0.83 for fatal CVD (95% CI, 0.76–0.92; I2=47.7%). The quality of the evidence assessed with the Grading of Recommendations Assessment, Development, and Evaluation tool ranged from very low to moderate, which was mainly driven by high between‐studies heterogeneity. Strengths of associations did not differ by mean age at study entry, median follow‐up duration, mean parity, level of adjustment, study quality, or geographical region. A progressive risk reduction of all CVD outcomes with lifetime durations of breastfeeding from 0 up to 12 months was found, with some uncertainty about shapes of associations for longer durations. Conclusions: Breastfeeding was associated with reduced maternal risk of CVD outcomes.”

Open access: https://www.ahajournals.org/doi/10.1161/JAHA.121.022746

New Study in JAMA Pediatrics Comparing Human Milk Antibody Induction, Persistence, and Neutralizing Capacity in SARS-CoV-2 Infection versus mRNA Vaccination

Title: Association of Human Milk Antibody Induction, Persistence, and Neutralizing Capacity With SARS-CoV-2 Infection vs mRNA Vaccination.

In: JAMA Pediatrics 2021 Nov 10. doi: 10.1001/jamapediatrics.2021.4897. Online ahead of print.

Authors: Bridget E Young, Antti E Seppo, Nichole Diaz, Casey Rosen-Carole, Anna Nowak-Wegrzyn, Joseline M Cruz Vasquez, Rita Ferri-Huerta, Phuong Nguyen-Contant, Theresa Fitzgerald, Mark Y Sangster, David J Topham, Kirsi M Järvinen.

Key Points:

"Question: How does human milk antibody composition and neutralization activity differ between lactating parents with COVID-19 infection vs those with COVID-19 messenger RNA vaccination?

"Findings: In this cohort study of a convenience sample of 47 lactating parents with infection and 30 lactating parents who were vaccinated, antibody response in milk after infection was IgA dominant and highly variable while vaccination was associated with a robust IgG response, which began to decline by 90 days after the second vaccine dose. Milk from both groups showed neutralization activity against live SARS-CoV-2 virus, which can be attributed to IgA and IgG SARS-CoV-2 antibodies.

"Meaning: COVID-19 infection and vaccination may result in significant antibodies in human milk that exhibit different temporal patterns, but both neutralize live SARS-CoV-2 virus."

From the abstract:

"Importance: Long-term effect of parental COVID-19 infection vs vaccination on human milk antibody composition and functional activity remains unclear.

"Objective: To compare temporal IgA and IgG response in human milk and microneutralization activity against SARS-CoV-2 between lactating parents with infection and vaccinated lactating parents out to 90 days after infection or vaccination.

"Design, setting, and participants: Convenience sampling observational cohort (recruited July to December 2020) of lactating parents with infection with human milk samples collected at days 0 (within 14 days of diagnosis), 3, 7, 10, 28, and 90. The observational cohort included vaccinated lactating parents with human milk collected prevaccination, 18 days after the first dose, and 18 and 90 days after the second dose.

"Exposures: COVID-19 infection diagnosed by polymerase chain reaction within 14 days of consent or receipt of messenger RNA (mRNA) COVID-19 vaccine (BNT162b2 or mRNA-1273). "Main outcomes and measures: Human milk anti-SARS-CoV-2 receptor-binding domain IgA and IgG and microneutralization activity against live SARS-CoV-2 virus.

"Results: Of 77 individuals, 47 (61.0%) were in the infection group (mean [SD] age, 29.9 [4.4] years), and 30 (39.0%) were in the vaccinated group (mean [SD] age, 33.0 [3.4] years; P = .002). The mean (SD) age of infants in the infection and vaccinated group were 3.1 (2.2) months and 7.5 (5.2) months, respectively (P < .001). Infection was associated with a variable human milk IgA and IgG receptor-binding domain-specific antibody response over time that was classified into different temporal patterns: upward trend and level trend (33 of 45 participants [73%]) and low/no response (12 of 45 participants [27%]). Infection was associated with a robust and quick IgA response in human milk that was stable out to 90 days after diagnosis. Vaccination was associated with a more uniform IgG-dominant response with concentrations increasing after each vaccine dose and beginning to decline by 90 days after the second dose. Vaccination was associated with increased human milk IgA after the first dose only (mean [SD] increase, 31.5 [32.6] antibody units). Human milk collected after infection and vaccination exhibited microneutralization activity. Microneutralization activity increased throughout time in the vaccine group only (median [IQR], 2.2 [0] before vaccine vs 10 [4.0] after the first dose; P = .003) but was higher in the infection group (median [IQR], 20 [67] at day 28) vs the vaccination group after the first-dose human milk samples (P = .002). Both IgA and non-IgA (IgG-containing) fractions of human milk from both participants with infection and those who were vaccinated exhibited microneutralization activity against SARS-CoV-2."

Conclusions and relevance in the abstract: "In this cohort study of a convenience sample of lactating parents, the pattern of IgA and IgG antibodies in human milk differed between COVID-19 infection vs mRNA vaccination out to 90 days. While infection was associated with a highly variable IgA-dominant response and vaccination was associated with an IgG-dominant response, both were associated with having human milk that exhibited neutralization activity against live SARS-CoV-2 virus."

Conclusion in the summary: "In this cohort study of lactating parents, SARS-CoV-2 mRNA vaccination was found to be associated with a robust IgG-predominant response in human milk that began to decline by 90 days after the second vaccine dose. This is in contrast to antibody response to infection, which was variable and IgA dominant with 73% of participants showing an upward or level trend in human milk antibodies out past 90 days after infection. Both illness and vaccination resulted in human milk with neutralization activity against live wild-type SARS-CoV-2. Our data suggest that both IgA and IgG contribute to the neutralizing capacity, implying clinical benefit to infants receiving human milk from parents with COVID-19 infection or who are vaccinated."

Open access: https://jamanetwork.com/journals/jamapediatrics/fullarticle/2786219


New Study: Women Who Breastfeed Exhibit Cognitive Benefits After Age 50

A new study from the University of California - Los Angeles (UCLA) found that women over the age of 50 who had breastfed their babies performed better on cognitive tests compared to women who had never breastfed, suggesting that breastfeeding may have a positive impact on postmenopausal women's cognitive performance, with long-term benefits for the mother's brain.

From the ScienceDaily press release:

"'While many studies have found that breastfeeding improves a child's long-term health and well-being, our study is one of very few that has looked at the long-term health effects for women who had breastfed their babies,'" said Molly Fox PhD, lead author of the study and an Assistant Professor in the UCLA Department of Anthropology and the Department of Psychiatry and Biobehavioral Sciences. "'Our findings, which show superior cognitive performance among women over 50 who had breastfed, suggest that breastfeeding may be 'neuroprotective' later in life.'"

"Key findings from the researchers' analysis of the data collected from questionnaires on the women's reproductive history revealed that about 65% of non-depressed women reported having breastfed, compared to 44% of the depressed women. All non-depressed participants reported at least one completed pregnancy compared to 57.8% of the depressed participants.

"Results from the cognitive tests also revealed that those who had breastfed, regardless of whether they were depressed or not, performed better in all four of the cognitive tests measuring for learning, delayed recall, executive functioning and processing compared to women who had not breastfed.

"Separate analyses of the data for the depressed and non-depressed groups also revealed that all four cognitive domain scores were significantly associated with breastfeeding in the women who were not depressed. But in the women who were depressed, only two of the cognitive domains -- executive functioning and processing speed -- were significantly associated with breastfeeding.

"Interestingly, the researchers also found that longer time spent breastfeeding was associated with better cognitive performance. When they added up all the time a woman spent breastfeeding in her life, they found that women who did not breastfeed had significantly lower cognitive scores in three out of four domains compared to women who had breastfed for 1-12 months, and in all four domains compared to the women who had breastfed for more than 12 months. Women who had breastfed the longest had the highest cognitive test scores."

Title: Women who breastfeed exhibit cognitive benefits after age 50.

In: Evolution, Medicine, and Public Health 2021; DOI: 10.1093/emph/eoab027

Authors: Molly Fox PhD, Prabha Siddarth PhD, Hanadi Ajam Oughli MD, Sarah A Nguyen MD, Michaela M Milillo BS, Yesenia Aguilar MS, Linda Ercoli PhD, Helen Lavretsky MD MS.

ScienceDaily press release: https://www.sciencedaily.com/releases/2021/10/211023122141.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fmind_brain%2Fchild_development+%28Child+Development+News+--+ScienceDaily%29

Accepted manuscript: https://academic.oup.com/emph/advance-article/doi/10.1093/emph/eoab027/6380138


New Papers

Title: Human Milk Endocannabinoid Levels as a Function of Obesity and Diurnal Rhythm.

In: Nutrients 2021 Jul; 13(7): 2297.

Authors: Palika Datta, Michael W. Melkus, Kathleen Rewers-Felkins, Dhavalkumar Patel, Tiffany Bateman, Teresa Baker, and Thomas W. Hale.

Abstract: "The endocannabinoid system is involved in the regulation of a variety of physiological and cognitive processes. While the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (N-arachidonoylethanolamine, AEA) have been found in breast milk, their role(s) have yet to be determined. This study determined the normal concentration ranges of endocannabinoids (2-AG and AEA) in breast milk and the influences, if any, of obesity and diurnal rhythms on their levels. Milk samples were collected from 36 breastfeeding mothers at 4–8 weeks postpartum at each feed over a 24-h period, and further stratified into three groups based on body mass index (BMI). The samples were analyzed using liquid chromatography mass spectrometry. AEA was below the limit of detection and 2-AG levels averaged 59.3 ± 18.3 ng/mL (± SD) in women with normal BMI. Wide-ranging 2-AG concentrations in the overweight (65.5 ± 41.9 ng/mL) /obese (66.1 ± 40.6 ng/mL) groups suggest BMI may be a contributing factor influencing its levels. Following a diurnal pattern, there was a significantly higher 2-AG concentration observed during the day, as compared to nighttime samples. In conclusion, our study clearly suggests that appropriate milk collection and storage conditions are critical. Further, body weight and diurnal rhythm appear to influence levels of 2-AG. Based on these results, future studies are underway to determine what specific roles endocannabinoids may play in human milk and how elevated levels of 2-AG may modulate infant appetite and health."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8308542/

Title: Monitoring breastfeeding indicators in high‐income countries: Levels, trends and challenges.

In: Maternal & Child Nutrition 2021 Jul; 17(3): e13137.

Authors: Juliana S. Vaz, corresponding author; Maria Fatima S. Maia, Paulo A. R. Neves, Thiago M. Santos, Luís Paulo Vidaletti, and Cesar Victora.

Abstract: "Monitoring indicators of breastfeeding practices is important to protect and evaluate the progress of breastfeeding promotion efforts. However, high‐income countries lack standardized methodology to monitor their indicators. We aimed to update and summarize nationally representative annual estimates of breastfeeding indicators in high‐income countries and to describe methodological issues pertaining to the data sources used. A review was conducted through population‐based surveys with nationally representative samples or health reports from nationally representative administrative data of electronic surveys or medical records. Methodological aspects and rates of all breastfeeding indicators available were summarized by country. The median and annual growth of breastfeeding in percentage points within countries with time‐series data were estimated. Data from 51 out of 82 high‐income countries were identified. The data were obtained through surveys (n = 32) or administrative data (n = 19). Seventy‐one percent of countries have updated their indicators since 2015. Ever breastfed was the indicator most frequently reported (n = 46), with a median of 91%. By 6 months of age, the median equals 18% for exclusive and 45% for any breastfeeding. At 12 months, the median of continued breastfeeding decreased to 29%. The annual growth rate for ever breastfed, exclusive and any breastfeeding at 6 months and continued at 12 months varied from 1.5 to −2.0, 3.5 to −3.1, 5.0 to −1.0 and 5.0 to −1.9, respectively, with positive changes for most countries. Stronger interventions are needed to promote breastfeeding in high‐income countries as a whole, and investments are required to monitor trends with standardized methodologies."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8189208/

Title: Guilt, shame, and postpartum infant feeding outcomes: A systematic review.

In: Maternal & Child Nutrition 2021 Jul; 17(3): e13141.

Authors: Leanne Jackson, corresponding author; Leonardo De Pascalis, Jo Harrold, and Victoria Fallon.

Abstract: "Negative maternal affect (e.g., depression and anxiety) has been associated with shorter breastfeeding duration and poorer breastfeeding intention, initiation, and exclusivity. Other affective states, including guilt and shame, have been linked with formula feeding practice, though existing literature has yet to be synthesised. A narrative synthesis of quantitative data and a framework synthesis of qualitative and quantitative data were conducted to explore guilt and/or shame in relation to infant feeding outcomes. Searches were conducted on the DISCOVER database between December 2017 and March 2018. The search strategy was rerun in February 2020, together yielding 467 studies. The study selection process identified 20 articles, published between 1997 and 2017. Quantitative results demonstrated formula feeders experienced guilt more commonly than breastfeeding mothers. Formula feeders experienced external guilt most commonly associated with healthcare professionals, whereas breastfeeding mothers experienced guilt most commonly associated with peers and family. No quantitative literature examined shame in relation to infant feeding outcomes, warranting future research. The framework synthesis generated four distinct themes which explored guilt and/or shame in relation to infant feeding outcomes: ‘underprepared and ineffectively supported’, ‘morality and perceived judgment’ (breastfeeding), ‘frustration with infant feeding care’ and ‘failures, fears and forbidden practice’ (formula feeding). Both guilt and shame were associated with self‐perception as a bad mother and poorer maternal mental health. Guilt and shame experiences were qualitatively different in terms of sources and outcomes, dependent on infant feeding method. Suggestions for tailored care to minimise guilt and shame, while supporting breastfeeding, are provided."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8189225/

Title: Maintaining human milk bank services throughout the COVID‐19 pandemic: A global response.

In: Maternal & Child Nutrition 2021 Jul; 17(3): e13131.

Authors: Natalie Shenker, corresponding author; Marta Staff, Amy Vickers, Joao Aprigio, Satish Tiwari, Sushma Nangia, Ruchika Chugh Sachdeva, Vanessa Clifford, Anna Coutsoudis, Penny Reimers, Kiersten Israel‐Ballard, Kimberly Mansen, Radmila Mileusnic‐Milenovic, Aleksandra Wesolowska, Johannes B. van Goudoever, Mohammadbagher Hosseini, Daniel Klotz, Anne Hagen Grøvslien, Gillian Weaver, and Virtual Collaborative Network of Milk Banks and Associations.

Abstract: "If maternal milk is unavailable, the World Health Organization recommends that the first alternative should be pasteurised donor human milk (DHM). Human milk banks (HMBs) screen and recruit milk donors, and DHM principally feeds very low birth weight babies, reducing the risk of complications and supporting maternal breastfeeding where used alongside optimal lactation support. The COVID‐19 pandemic has presented a range of challenges to HMBs worldwide. This study aimed to understand the impacts of the pandemic on HMB services and develop initial guidance regarding risk limitation. A Virtual Collaborative Network (VCN) comprising over 80 HMB leaders from 36 countries was formed in March 2020 and included academics and nongovernmental organisations. Individual milk banks, national networks and regional associations submitted data regarding the number of HMBs, volume of DHM produced and number of recipients in each global region. Estimates were calculated in the context of missing or incomplete data. Through open‐ended questioning, the experiences of milk banks from each country in the first 2 months of the pandemic were collected and major themes identified. According to data collected from 446 individual HMBs, more than 800,000 infants receive DHM worldwide each year. Seven pandemic‐related specific vulnerabilities to service provision were identified, including sufficient donors, prescreening disruption, DHM availability, logistics, communication, safe handling and contingency planning, which were highly context‐dependent. The VCN now plans a formal consensus approach to the optimal response of HMBs to new pathogens using crowdsourced data, enabling the benchmarking of future strategies to support DHM access and neonatal health in future emergencies."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883204/

Save the Date: Breastfeeding Grand Rounds 2021 at the University at Albany State University of New York

For many years, it has been an annual and joyful event to view Breastfeeding Grand Rounds with Dr. Ruth Lawrence and her guests. This webcast is sponsored by the University at Albany School of Public Health Center for Public Health Continuing Education, in partnership with the New York State Department of Health Women, Infants and Children (WIC) Program. Breastfeeding Grand Rounds webcasts feature experts in clinical and public health to provide education on current breastfeeding health issues with both clinical and public health significance. Continuing education credits have been historically and generously awarded without a fee to those who complete the attendance criteria (complete an evaluation and post-test with a score of 80% and above on the post-test).

Date: November 4, 2021

Time: 8:30am - 10:30am Eastern Time

Topic: Marijuana and Breastfeeding

Further details to be announced at https://www.albany.edu/cphce/bfgr.shtml

To view past Breastfeeding Grand Rounds webcasts, please see the links below:

Topic: Community Breastfeeding Support in the Time of Public Health Emergencies

Originally presented on December 22, 2020.

L-CERPs are offered until December 22, 2021.

Nursing Contact Hours are offered until February 28, 2022.

Continuing Medical Education Contact Hours are offered until December 31, 2023.

Additional past Breastfeeding Grand Rounds webcasts:

Breastfeeding Recommendations for Women Impacted by Opioid Use Disorder and Infants with Neonatal Abstinence Syndrome (originally presented on 8/1/19)

Increasing Skin-To-Skin Contact to Improve Perinatal Outcomes and Breastfeeding Success (originally presented on 8/2/2018)

On Length of Consults

The topics of consult length and insurance billing are discussed periodically here and on professional social media sites. I offer this viewpoint: Many consults are to assist the dyad with the baby’s motor learning toward motor control at the breast, and also to support the milk supply until the infant can drive the volume. Of course our profession addresses all that is related to lactation and infant feeding, and so much is about assisting the baby in becoming skilled at the breast. Consider that occupational therapists work twice daily with adult inpatients in rehabilitation facilities for the reacquisition of patients’ self-feeding skills. These twice-daily OT visits take place once in the morning and once in the afternoon, typically for at least two weeks and longer as needed. Most adult patients who are relearning feeding skills in rehabilitation facilities are receiving further care after a stroke or traumatic brain injury. Both members of the nursing dyad deserve at least as much time as one adult patient in a rehab facility who routinely receives professional support from OT for the reacquisition of self-feeding skills. In nursing dyads, there are two patients — not one patient per consult, unless the consult addresses a concern with only one member of the dyad, such as in mastitis. Two patients during one consult often warrant more time spent in the consult. Imagine the good that our profession could do if outpatient consults took place daily in instances of the baby’s motor learning toward motor control, as well as in other instances that warrant more frequent follow-up. This is not to say that daily consults should occur for weeks or months without end, but in the early days of skill acquisition for feeding skills, the professional time that is allotted to adult rehab patients who are relearning feeding skills should also be granted and tailored to the youngest patients who are just beginning their learning in how to feed.

New Study on Improved Cognitive Performance in Children Ages 9-10 Who Were Breastfed

New study from the University of Rochester:

Title: Breastfeeding Duration Is Associated With Domain-Specific Improvements in Cognitive Performance in 9–10-Year-Old Children.

In: Frontiers in Public Health: Children and Health 26 April 2021 https://doi.org/10.3389/fpubh.2021.657422

Authors: Daniel A. Lopez, John J. Foxe, Yunjiao Mao, Wesley K. Thompson, Hayley J. Martin and Edward G. Freedman.

Abstract: "Significant immunological, physical and neurological benefits of breastfeeding in infancy are well-established, but to what extent these gains persist into later childhood remain uncertain. This study examines the association between breastfeeding duration and subsequent domain-specific cognitive performance in a diverse sample of 9–10-year-olds enrolled in the Adolescent Brain Cognitive Development (ABCD) Study®. The analyses included 9,116 children that attended baseline with their biological mother and had complete neurocognitive and breastfeeding data. Principal component analysis was conducted on data from an extensive battery of neurocognitive tests using varimax-rotation to extract a three-component model encompassing General Ability, Executive Functioning, and Memory. Propensity score weighting using generalized boosted modeling was applied to balance the distribution of observed covariates for children breastfed for 0, 1–6, 7–12, and more than 12 months. Propensity score-adjusted linear regression models revealed significant association between breastfeeding duration and performance on neurocognitive tests representing General Ability, but no evidence of a strong association with Executive Function or Memory. Benefits on General Ability ranged from a 0.109 (1–6 months) to 0.301 (>12 months) standardized beta coefficient difference compared to those not breastfed. Results indicate clear cognitive benefits of breastfeeding but that these do not generalize to all measured domains, with implications for public health policy as it pertains to nutrition during infancy."

Open access: https://www.frontiersin.org/articles/10.3389/fpubh.2021.657422/full

ScienceDaily news release: https://www.sciencedaily.com/releases/2021/04/210427110611.htm

New Studies

Title: Human milk mycotoxin contamination: smoking exposure and breastfeeding problems.

In: The Journal of Maternal-Fetal and Neonatal Medicine 2021 Jan;34(1):31-40. doi: 10.1080/14767058.2019.1586879.

Authors: Esra Yasemin Memiş, Sıddıka Songül Yalçın.

Abstract: "Purpose: Mammalian milk may contain pollutants as a result of the maternal exposure. The objective was to determine the presence of selected mycotoxins in human milk and to investigate the effect of maternal characteristics on breastmilk mycotoxin levels and to examine the effect of mycotoxin contamination on lactational problems. Materials and methods: Information about maternal characteristics were taken by a questionnaire and breast milk samples were collected. Levels of aflatoxins M1 (AFM1), ochratoxins A (OTA), zearalenone (ZEN), Deoxynivalenol (DON) were determined by the solid-phase direct competitive enzyme immunoassay. Results: Median levels of breast milk AFM1 and OTA was 3.07 pg/mL and 1.38 ng/mL, respectively. ZEN and DON levels were higher than 0.3 ng/mL in 59% and higher than 10 ng/mL in 37.7%. After controlling for confounding factors, mothers who experienced ‘delayed onset of lactogenesis’ had odds 3.33 times more for the highest quartile of ZEN and mothers with cracked nipples had odds 8.36 times more for the highest quartile of DON. Multiple regression analysis revealed that smoking exposure (environmental, maternal smoking versus never) significantly affected being in the highest quartile of OTA. Conclusion: Mycotoxin can pass to breast milk and smoking exposure of the mother may influence this situation. Mycotoxin exposure may lead to lactation problems. Maternal and infant health can be protected by preventing smoking exposure."

Abstract only: https://www.tandfonline.com/doi/abs/10.1080/14767058.2019.1586879?journalCode=ijmf20

Title: Persistence of Δ-9-Tetrahydrocannabinol in Human Breast Milk.

In: JAMA Pediatrics, 2021; DOI:10.1001/jamapediatrics.2020.6098

Authors: Erica M. Wymore; Claire Palmer; George S. Wang; Torri D. Metz; David W. A. Bourne; Cristina Sempio; Maya Bunik.

Abstract: "Δ-9-Tetrahydrocannabinol (THC) crosses the placenta, is highly lipophilic, and can be detected in breast milk. National guidelines recommend abstinence from marijuana use during pregnancy and lactation, with limited data regarding the presence of THC in breast milk. We aimed to estimate the amount and duration of THC excretion in breast milk among women with known prenatal marijuana use."

Excerpts from the ScienceDaily news release: "In a new study published in JAMA Pediatrics, researchers at Children's Hospital Colorado (Children's Colorado) have found that tetrahydrocannabinol (THC), the psychoactive component of marijuana, stays in breast milk for up to six weeks, further supporting the recommendations of the American Academy of Pediatrics, the American College of Obstetricians and Gynecologists and the Academy of Breastfeeding Medicine to abstain from marijuana use during pregnancy and while a mother is breastfeeding. This is the first study examining THC in breastmilk and plasma among women with known marijuana use in pregnancy since a 1982 study in the New England Journal of Medicine." "'This study provided invaluable insight into the length of time it takes a woman to metabolize the THC in her body after birth, but it also helped us understand why mothers use marijuana in the first place,' said Maya Bunik, MD, MPH, senior investigator, medical director of the Child Health Clinic and the Breastfeeding Management Clinic at Children's Colorado and professor of pediatrics at the CU School of Medicine. 'To limit the unknown THC effects on fetal brain development and promote safe breastfeeding, it is critical to emphasize marijuana abstention both early in pregnancy and postpartum. To help encourage successful abstention, we need to look at -- and improve -- the system of supports we offer new moms.'"

"Longitudinal studies from the 1980s have shown that children born to mothers who used marijuana during pregnancy experienced long-term issues with cognitive and executive functioning, including impulsivity, as well as deficits in learning, sustained attention and visual problem-solving skills."

ScienceDaily news release: https://www.sciencedaily.com/releases/2021/03/210308131719.htm

Abstract only: https://jamanetwork.com/journals/jamapediatrics/article-abstract/2776975

Title: Vegan or vegetarian diet and breast milk composition - a systematic review.

In: Critical Reviews in Food Science and Nutrition 2021;61(7):1081-1098. doi: 10.1080/10408398.2020.1753650.

Authors: Karolina Karcz, Barbara Królak-Olejnik.

Abstract: "It is known that nutritional composition of breast milk is, to a certain extent, related to maternal diet. The question of nutritional adequacy of mothers’ milk is often raised whenever a vegetarian or vegan diet during the lactation process is concerned. For this reason, in some countries, the recruitment of vegan lactating women as milk donors is excluded by milk banks. The purpose of this systematic review is to summarize existing knowledge on variability of specific nutrients in breastmilk of mothers adhering to a plant-based diet. The databases, including MEDLINE (Pubmed) and Scopus, were used to identify relevant publications. Data extraction and analysis were conducted following a PRISMA protocol. Thirteen publications concerning the impact of dietary pattern and levels of animal-origin food intake on breast milk composition were included. The systematic review has shown that all non-vegetarian, vegetarian and vegan mothers produce breast milk of comparable nutritional value. Several differences are primarily attributed to fatty acids and some micro-components, primarily vitamin B12. Regardless of dietary choices, nourishment and adequate nutrition have a significant impact on human milk composition – on the basis of the current evidence, vegetarian and vegan mothers are capable of producing nutritionally valuable milk for their infants, as far as the appropriate supplementation compensating for breastfeeding mother’s nutritional requirements is provided. Dietary choices should not be a permanent exclusion criterion for donor candidates in human milk banks."

Abstract only: https://www.tandfonline.com/doi/abs/10.1080/10408398.2020.1753650?journalCode=bfsn20

New Study on Maternal Depression and Affection in the Breastfeeding Dyad

Title: Affectionate Touch in the Context of Breastfeeding and Maternal Depression Influences Infant Neurodevelopmental and Temperamental Substrates.

In: Neuropsychobiology, 2021; 1 DOI: 10.1159/000511604

Authors: Hardin J.S. · Jones N.A. · Mize K.D. · Platt M.

Abstract: “Background: While numerous studies have demonstrated maternal depression’s influence on infant brain development, few studies have examined the changes that occur as a consequence of co-occurring experiential factors that affect quality of mother and infant affectionate touch as well as infant temperament and neurophysiological systems. The aim of the study was to examine the interactive effects of maternal depression and breastfeeding on mother and infant affectionate touch and infant temperament and cortical maturation patterns across early development. Methods: 113 mothers and their infants participated when infants were 1 and 3 months of age. Questionnaires to assess maternal depressive symptoms, feeding, and temperament were completed. Tonic EEG patterns (asymmetry and left and right activity) were collected and the dyads were video-recorded during feeding to assess mother and infant affectionate touch patterns. Results: Data analysis showed that EEG activity and mother-infant affectionate touch differed as a function of mood and feeding method. Notably, only infants of depressed mothers that bottle-fed showed right frontal EEG asymmetry and attenuated change in the left frontal region across 3 months. Breastfeeding positively impacted affectionate touch behaviors and was associated with increased left and decreased right frontal EEG activation even for depressed groups. Furthermore, a model incorporating physiology, maternal depression, touch, temperament, and feeding indicated significant prediction for infant affectionate touch (with breastfeeding and affectively positive temperament demonstrating the strongest prediction). Con­clusion: The findings suggest that breastfeeding and the infant’s positive temperament influence mother-infant affectionate touch patterns and result in neuroprotective outcomes for infants, even those exposed to maternal depression within early development.”

ScienceDaily news release on this study: https://www.sciencedaily.com/releases/2021/02/210210091209.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fmind_brain%2Finfant_and_preschool_learning+%28Infant+and+Preschool+Learning+News+--+ScienceDaily%29

Open access: DOI: 10.1159/000511604

New Papers on Oxytocin & Prolactin

Title: Is Oxytocin "Nature's Medicine"?

In: Pharmacological Reviews 2020 Oct;72(4):829-861. doi: 10.1124/pr.120.019398.

Authors: C Sue Carter, William M Kenkel, Evan L MacLean, Steven R Wilson, Allison M Perkeybile, Jason R Yee, Craig F Ferris, Hossein P Nazarloo, Stephen W Porges, John M Davis, Jessica J Connelly, Marcy A Kingsbury.

Abstract: “Oxytocin is a pleiotropic, peptide hormone with broad implications for general health, adaptation, development, reproduction, and social behavior. Endogenous oxytocin and stimulation of the oxytocin receptor support patterns of growth, resilience, and healing. Oxytocin can function as a stress-coping molecule, an anti-inflammatory, and an antioxidant, with protective effects especially in the face of adversity or trauma. Oxytocin influences the autonomic nervous system and the immune system. These properties of oxytocin may help explain the benefits of positive social experiences and have drawn attention to this molecule as a possible therapeutic in a host of disorders. However, as detailed here, the unique chemical properties of oxytocin, including active disulfide bonds, and its capacity to shift chemical forms and bind to other molecules make this molecule difficult to work with and to measure. The effects of oxytocin also are context-dependent, sexually dimorphic, and altered by experience. In part, this is because many of the actions of oxytocin rely on its capacity to interact with the more ancient peptide molecule, vasopressin, and the vasopressin receptors. In addition, oxytocin receptor(s) are epigenetically tuned by experience, especially in early life. Stimulation of G-protein-coupled receptors triggers subcellular cascades allowing these neuropeptides to have multiple functions. The adaptive properties of oxytocin make this ancient molecule of special importance to human evolution as well as modern medicine and health; these same characteristics also present challenges to the use of oxytocin-like molecules as drugs that are only now being recognized. SIGNIFICANCE STATEMENT: Oxytocin is an ancient molecule with a major role in mammalian behavior and health. Although oxytocin has the capacity to act as a "natural medicine" protecting against stress and illness, the unique characteristics of the oxytocin molecule and its receptors and its relationship to a related hormone, vasopressin, have created challenges for its use as a therapeutic drug.”

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7495339/

Title: An Emerging Role for Prolactin in Female-Selective Pain.

In: Trends in Neuroscience 2020 Aug;43(8):635-648. doi: 10.1016/j.tins.2020.06.003.

Authors: Yanxia Chen, Edita Navratilova, David W. Dodick, Frank Porreca.

“Highlights: Women display a higher prevalence of many pain conditions, suggesting a role for sexually dimorphic pain mechanisms. Emerging evidence implicates the prolactin (PRL) and prolactin receptor (PRLR) system as a female-selective mechanism promoting pain in females. PRL signals differentially through long and short PRLR (PRLR-L and PRLR-S) that reciprocally inhibit PRL signaling. Increased nociceptor excitability and pain result from PRL signaling through PRLR-S. Dysregulation of PRLR isoforms in pathological states may provide a basis for female-prevalent pain disorders, and allow the development of therapeutic strategies for improved treatment of pain in women.”

Abstract: “Women experience many pain conditions more frequently when compared with men, but the biological mechanisms underlying sex differences in pain remain poorly understood. In particular, little is known about possible sex differences in peripheral nociceptors, the fundamental building blocks of pain transmission. Emerging evidence reveals that prolactin (PRL) signaling at its cognate prolactin receptor (PRLR) in primary afferents promotes nociceptor sensitization and pain in a female-selective fashion. In this review, we summarize recent progress in understanding the female-selective role of PRL/PRLR in nociceptor sensitization and in pathological pain conditions, including postoperative, inflammatory, neuropathic, and migraine pain, as well as opioid-induced hyperalgesia. The clinical implications of the peripheral PRL/PRLR system for the discovery of new therapies for pain control in women are also discussed.”

Abstract: DOI:https://doi.org/10.1016/j.tins.2020.06.003

Title: Prolactin: A hormone with diverse functions from mammary gland development to cancer metastasis.

In: Seminars in Cell & Developmental Biology 2020 Oct 24;S1084-9521(20)30164-6.

Authors: Ödül Karayazi Atıcı PhD, Nayantara Govindrajan, Isbel Lopetegui-González, Carrie S.Shemanko.

Abstract: “Prolactin has a rich mechanistic set of actions and signaling in order to elicit developmental effects in mammals. Historically, prolactin has been appreciated as an endocrine peptide hormone that is responsible for final, functional mammary gland development and lactation. Multiple signaling pathways impacted upon by the microenvironment contribute to cell function and differentiation. Endocrine, autocrine and paracrine signaling are now apparent in not only mammary development, but also in cancer, and involve multiple cell types including those of the immune system. Multiple ligands agonists are capable of binding to the prolactin receptor, potentially expanding receptor function. Prolactin has an important role not only in tumorigenesis of the breast, but also in a number of hormonally responsive cancers such as prostate, ovarian and endometrial cancer, as well as pancreatic and lung cancer. Although pituitary and extra-pituitary sources of prolactin such as the epithelium are important, stromal sourced prolactin is now also being recognized as an important factor in tumor progression, all of which potentially signal to multiple cell types in the tumor microenvironment. While prolactin has important roles in milk production including calcium and bone homeostasis, in the disease state it can also affect bone homeostasis. Prolactin also impacts metastatic cancer of the breast to modulate the bone microenvironment and promote bone damage. Prolactin has a fascinating contribution in both physiologic and pathologic settings of mammals.”

Abstract: https://www.sciencedirect.com/science/article/abs/pii/S1084952120301646?via%3Dihub

The Impact of Oxytocin on the Brain's Reward Center

Thinking of flow confusion and flow preference feeding behaviors led me to an online search in regard to the impact of food on the reward center in the brain. There are many published studies in this area, including those on eating disorders and much more. This 2018 paper from Germany and the UK was one of many studies that piqued my interest: Title: Oxytocin curbs calorie intake via food-specific increases in the activity of brain areas that process reward and establish cognitive control. In: Scientific Reports 2018 Feb 9;8(1):2736. doi: 10.1038/s41598-018-20963-4. Authors: Maartje S Spetter, Gordon B Feld, Matthias Thienel, Hubert Preissl, Maike A Hege, Manfred Hallschmid. Abstract: "The hypothalamic neurohormone oxytocin decreases food intake via largely unexplored mechanisms. We investigated the central nervous mediation of oxytocin's hypophagic effect in comparison to its impact on the processing of generalized rewards. Fifteen fasted normal-weight, young men received intranasal oxytocin (24 IU) or placebo before functional magnetic resonance imaging (fMRI) measurements of brain activity during exposure to food stimuli and a monetary incentive delay task (MID). Subsequently, ad-libitum breakfast intake was assessed. Oxytocin compared to placebo increased activity in the ventromedial prefrontal cortex, supplementary motor area, anterior cingulate, and ventrolateral prefrontal cortices in response to high- vs. low-calorie food images in the fasted state, and reduced calorie intake by 12%. During anticipation of monetary rewards, oxytocin compared to placebo augmented striatal, orbitofrontal and insular activity without altering MID performance. We conclude that during the anticipation of generalized rewards, oxytocin stimulates dopaminergic reward-processing circuits. In contrast, oxytocin restrains food intake by enhancing the activity of brain regions that exert cognitive control, while concomitantly increasing the activity of structures that process food reward value. This pattern points towards a specific role of oxytocin in the regulation of eating behaviour in humans that might be of relevance for potential clinical applications." Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5807408/

New Study on Immune System Support in Breastfed Infants

A new study from the University of Birmingham and Birmingham Women's and Children's NHS Foundation Trust:

Title: Breastfeeding promotes early neonatal regulatory T cell expansion and immune tolerance of non‐inherited maternal antigens.

In: Allergy 2021. doi:10.1111/all.14736

Authors: HL Wood, A Acharjee, H Pearce, MN Quraishi, RM Powell, AE Rossiter, AD Beggs, AK Ewer, P Moss, G Toldi.

From the ScienceDaily press release:

"Research led by the University of Birmingham and Birmingham Women's and Children's NHS Foundation Trust has revealed new insight into the biological mechanisms of the long-term positive health effects of breastfeeding in preventing disorders of the immune system in later life.

"Breastfeeding is known to be associated with better health outcomes in infancy and throughout adulthood, and previous research has shown that babies receiving breastmilk are less likely to develop asthma, obesity, and autoimmune diseases later in life compared to those who are exclusively formula fed.

"However, up until now, the immunological mechanisms responsible for these effects have been very poorly understood. In this new study, researchers have for the first time discovered that a specific type of immune cells -- called regulatory T cells -- expand in the first three weeks of life in breastfed human babies and are nearly twice as abundant as in formula fed babies. These cells also control the baby's immune response against maternal cells transferred with breastmilk and help reduce inflammation.

"Moreover, the research -- supported by the National Institute for Health Research's Surgical Reconstruction and Microbiology Research Centre (NIHR SRMRC) -- showed that specific bacteria, called Veillonella and Gemella, which support the function of regulatory T cells, are more abundant in the gut of breastfed babies. The results of the study, published in Allergy, emphasise the importance of breastfeeding, say the researchers.

"Senior author Gergely Toldi, researcher at the University of Birmingham and consultant neonatologist at Birmingham Women's and Children's NHS Foundation Trust, said: 'The influence of the type of milk received on the development of the immune response has not previously been studied in the first few weeks of life.'"

"'Prior to our research, the outstanding importance and the early involvement of this specific cell type in breastfed babies was unknown.'"

"'We hope this invaluable new insight will lead to an increase in rates of breastfeeding and will see more babies benefit from the advantages of receiving breastmilk.'"

"'Furthermore, we hope for those babies who are formula fed, these results will contribute to optimising the composition of formula milk in order to exploit these immunological mechanisms.'"

"'We are very grateful for the mums and babies who contributed to this special project.'"

"The study is the culmination of a unique three-year research project analysing data from 38 healthy mothers and their healthy babies. Small amounts of blood and stool samples were collected at birth at Birmingham Women's Hospital and then again later during home visits when the babies were three weeks old. Sixteen out of the 38 babies (42%) were exclusively breastfed for the duration of the study, while nine babies received mixed feeding, and 13 babies were exclusively formula-fed. "The researchers hope to now further study this biological mechanism in sick and pre-term newborn babies who have developed inflammatory complications."

ScienceDaily: https://www.sciencedaily.com/releases/2021/01/210114111912.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fhealth_medicine%2Fbreastfeeding+%28Breastfeeding+News+--+ScienceDaily%29

Open access: https://onlinelibrary.wiley.com/doi/epdf/10.1111/all.14736


New Studies

Title: Human Milk Retains Important Immunologic Properties After Defatting.

In: Journal of Parenteral and Enteral Nutrition 2020 Jul;44(5):904-911. doi: 10.1002/jpen.1722. Epub 2019 Oct 9.

Authors: Brittany Anne Jackson MD, Brigid Ellen Gregg MD, Sara Denise Tutor RDN, Jennifer Rachelle Bermick MD, Kate Peterson Stanley MD.

Abstract "Background: In neonatal chylothorax, thoracic lymphatic drainage is ineffective. The resultant effusions often require drainage, leading to a loss of immune components. Affected infants can be managed with formula or defatted human milk feedings low in long‐chain triglycerides to decrease lymph production. We hypothesized that there is no significant difference in the immunological profile or antibacterial effect of full‐fat and defatted human milk. Methods: Milk from lactating mothers was divided into 1 aliquot that was defatted via centrifugation with the full‐fat aliquot as control. Macronutrient content was analyzed with mid‐infrared spectroscopy. Flow cytometry was used to measure immune cell populations. Lactoferrin, lysozyme, immunoglobulin (Ig)A, and IgG values were determined using enzyme‐linked immunosorbent assay. The antibacterial properties were determined by inoculating paired full‐fat and defatted milk samples with Escherichia coli or Streptococcus pneumoniae bacteria and performing colony counts. Results: Compared with full‐fat milk, defatted milk demonstrated decreased total energy and fat and increased carbohydrate concentrations. Defatted milk demonstrated a significant decrease in all immune cell populations. There was no difference in IgA, IgG, lysozyme, or lactoferrin concentrations. Both aliquots demonstrated equivalent growth inhibition of E. coli and S. pneumoniae. Conclusions: Unexpectedly, defatted human milk contained significantly less leukocytes than full‐fat milk. IgA, IgG, lysozyme, and lactoferrin concentrations were preserved. The ability of defatted milk to inhibit bacterial growth was unaffected, suggesting that the antibacterial benefits of human milk remain after the defatting process. Further investigation regarding the clinical effect of leukocyte loss in defatted milk is warranted." Abstract only: https://onlinelibrary.wiley.com/doi/abs/10.1002/jpen.1722

Title: Origins of human milk microbiota: new evidence and arising questions.

In: Gut Microbes 2020 Nov 9;12(1):1667722. doi: 10.1080/19490976.2019.1667722. Published online: 04 Nov 2019.

Authors: Shirin Moossavi, Meghan B Azad.

Abstract: "Human milk contains a diverse community of bacteria. The growing appreciation of commensal microbes and increasing availability of high-throughput technology has set the stage for a theory-driven approach to the study of milk microbiota, and translation of this knowledge to improve maternal and child health. We recently profiled the milk microbiota of healthy Canadian mothers and applied theory-driven causal modeling, finding that mode of breast milk feeding (nursing directly at the breast vs. pumping and feeding breast milk from a bottle) was significantly associated with milk microbiota composition. This observation could reflect an increased exposure to pumps and/or a decreased exposure to the infant mouth. Either way, it provides evidence for the retrograde mechanism of milk inoculation. Here, we discuss the implications of this research and related controversies, and raise new questions about the origins and function of milk bacteria."

Open access: https://www.tandfonline.com/doi/full/10.1080/19490976.2019.1667722

Title: Early versus Delayed Fortification of Human Milk in Preterm Infants: A Systematic Review.

In: Neonatology 2020;117:24–32.

Authors: Alyahya W, Simpson J, Garcia AL, Mactier H, Edwards CA.

Abstract: "Expressed breast milk (EBM) is commonly supplemented with commercially prepared human milk fortifier to meet the additional nutritional needs of preterm infants. The optimal milk intake at which to introduce fortification is unknown. The objective of this systematic review was to compare the effect of early fortification (EF) versus that of delayed introduction of human milk fortifier (DF) on short-term outcomes including growth, feeding intolerance, length of hospital stay, and maturity at discharge in very-low-birth-weight infants. The search was carried out until March 2019 using 5 electronic databases (PubMed, Ovid Medline, Web of Science, Ovid Embase, and the Cochrane Library). The search was supplemented with a search of the clinical trial registry and reference lists. Eligible studies involved randomized controlled trials that had been designed to compare EF against DF using multi-nutrient fortifier for infants of a birth weight of <1,500 g who were fed exclusively or predominantly EBM. Four authors independently screened the studies for eligibility. A total of 1,972 articles were screened; 2 studies met the inclusion criteria and were included with a total number of participants of 171. The definition of EF and DF was not consistent between the 2 studies. There was no significant impact of EF versus DF on all outcomes. In conclusion, current data are limited and do not provide evidence on the optimal time to start fortification. The definition of EF and DF needs to be agreed upon and further larger randomized controlled trials are required."

Open access: https://www.karger.com/Article/FullText/501279