Reliability of Maternal Recall of Feeding at the Breast and Breast Milk Expression 6 Years After Delivery

Effects of Different Thawing and Warming Processes on Human Milk Composition

The composition of human milk is influenced by storage and processing practices. The effects of thawing and warming practices on human milk composition remain poorly studied despite their prevalence in home, research, and donor milk bank settings. This review comprehensively examines the impact of different thawing and warming methods on nutritional and bioactive human milk components. While some components such as carbohydrates and minerals remain stable under most typical thawing and warming conditions, others, such as fat, immune proteins, bacterial and human cells, and peptide amine hormones, are sensitive to warming. This review has identified that the data on the effects of milk thawing and warming is limited and often contradictory. Given that numerous important components of milk are diminished during cold storage, it is important that thawing and warming practices do not lead to further loss of or alterations to beneficial milk components. Further work in this field will facilitate greater standardization of thawing methods among researchers and underpin recommendations for thawing and warming of expressed milk for parents.

Plasma concentrations of per- and polyfluoroalkyl substances in pregnancy and breastfeeding duration in Project Viva

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) may disrupt mammary gland development and function; thereby inhibiting milk supply and breastfeeding duration. However, conclusions on the potential effects of PFAS and breastfeeding duration are limited by prior epidemiologic studies that inconsistently adjusted for past cumulative breastfeeding duration and by a lack of examination of the joint effects of PFAS mixtures.

METHODS

In Project Viva, a longitudinal cohort that enrolled pregnant participants from 1999 to 2002 in the greater Boston, MA area, we studied 1079 women who ever attempted to lactate. We investigated associations of plasma concentrations of select PFAS in early pregnancy (mean: 10.1 weeks gestation) with breastfeeding termination by 9 months, after which women typically cite self-weaning as the reason for terminating breastfeeding. We used Cox regression for single-PFAS models and quantile g-computation for mixture models, adjusting for sociodemographics, prior breastfeeding duration, and weeks of gestation at the time of blood draw.

RESULTS

We detected 6 PFAS [perfluorooctane sulfonate; perfluorooctanoate (PFOA); perfluorohexane sulfonate; perfluorononanoate; 2-(N-ethyl-perfluorooctane sulfonamido) acetate (EtFOSAA); 2-(N-methyl-perfluorooctane sulfonamide) acetate (MeFOSAA)] in >98 % of samples. Sixty percent of lactating women terminated breastfeeding by 9 months postpartum. Women with higher plasma concentrations of PFOA, EtFOSAA, and MeFOSAA had a greater hazard of terminating breastfeeding in the first 9 months postpartum [HR (95 % CI) per doubling concentration: 1.20 (1.04, 1.38) for PFOA; 1.10 (1.01, 1.20) for EtFOSAA; 1.18 (1.08, 1.30) for MeFOSAA]. In the quantile g-computation model, simultaneously increasing all PFAS in the mixture by one quartile was associated with 1.17 (95 % CI: 1.05, 1.31) greater hazard of terminating breastfeeding in the first 9 months.

CONCLUSION

Our findings suggest that exposure to PFAS may be associated with reduced breastfeeding duration and draw further attention to environmental chemicals that may dysregulate human lactation.

Childhood pneumonia in Beijing: Associations and interactions among selected demographic and environmental factors

Among infectious diseases, pneumonia is the greatest cause of mortality in children less than 5 years old. Approximately 27% of Beijing's 3-8 year-old children have had pneumonia at least once. The sole reservoir of pneumonia pathogens is the human nasopharynx. We investigated associations and interactions among two kinds of environmental risk factors: i) airborne pathogens, namely closed bedroom window and shared bedroom and ii) pollutants, namely traffic pollution and environmental tobacco smoke (ETS). We evaluated breastfeeding's (BF) protective value against childhood pneumonia. The database consists of responses to a questionnaire in a cross-sectional study. Crude and adjusted Odds Ratios were assessed independently for each risk factor. Combinations of the studied risk factors were analyzed using multivariate logistic regression. Risk factors were evaluated for interactions on the additive scale using the metrics Relative Excess Risk due to Interaction (RERI), Attributable Proportion (AP) and Synergy Index (S). All independent risk factors were significant for children's pneumonia. We also found evidence of possible synergistic interaction between pairs of risk factors that was stronger when one of the risk factors was a closed bedroom window. Remarkably, window opening was associated with reduced risk of pneumonia for children living near heavy traffic pollution. Longer duration BF was more protective than shorter, and exclusive BF was more protective than partial BF against childhood pneumonia. In conclusion, low ventilation (closed bedroom windows), shared bedroom, ETS, and traffic exposure were associated with increased risk of pneumonia. Exclusive BF for more than six months had the greatest protective value against pneumonia.

A Quasi-Experimental Assessment of the Effect of the 2009 WIC Food Package Revisions on Breastfeeding Outcomes

Breastfeeding rates among infants participating in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) are consistently lower than those of WIC nonparticipants. The 2009 WIC food package revisions were intended to incentivize breastfeeding among the WIC population. To examine the effectiveness of this policy change, we estimated an intent-to-treat regression-adjusted difference-in-difference model with propensity score weighting, an approach that allowed us to control for both secular trends in breastfeeding and selection bias. We used novel data from the Feeding Infants and Toddlers Survey from 2008 and 2016. We defined our treatment group as infants eligible for WIC based on household income and our control group as infants in households with incomes just above the WIC eligibility threshold. The breastfeeding outcomes we analyzed were whether the infants were ever breastfed, breastfed through 6 months, and breastfed exclusively through 6 months. We observed significant increases in infants that were ever breastfed in both the treatment group (10 percentage points; p < 0.01) and the control group (15 percentage points; p < 0.05); however, we did not find evidence that the difference between the two groups was statistically significant, suggesting that the 2009 revisions may not have had an effect on any of these breastfeeding outcomes.

Searching for a Relationship between Early Breastfeeding and Cognitive Development of Attention and Working Memory Capacity

Previous research consistently reported that subjects that were exclusively breastfed (eBF) vs. not-exclusively breastfed (neBF) during infancy (0-6 months) showed increased scores of general intelligence measures (e.g., the intelligence quotient). However, the existent literature largely neglected whether breastfeeding also affects specific cognitive processes, such as attention and working memory (WM) capacity. We tested whether eBF vs. neBF subjects showed performance differences in relation to these two core cognitive functions. The Attention Network Test (ANT), to measure alerting, orienting, and conflict, and the Change Colour Task (CCT), to measure visuospatial WM capacity, were administered to 144 participants divided according to age (6-, 10-, and 18-year-old participants) and breastfeeding (eBF or neBF during 0-6 months of life). Importantly, the sub-groups were homogenous in terms of maternal education, a factor potentially affecting the relation between breastfeeding and cognition. While we found increased performance as a function of participants' age in both tasks, we failed to observe effects related to breastfeeding, as evidenced by Bayesian analyses. These findings highlight for the first time that the pattern of nutrition provided during early infancy does not appear to affect the development of attention and WM capacity, at least starting from the age considered in the present study.

The association between duration of breastfeeding and childhood asthma outcomes

BACKGROUND

Postnatal exposures, including breastfeeding, may influence asthma development.

OBJECTIVE

To investigate the association between breastfeeding duration and child asthma.

METHODS

We studied 2021 mother-child dyads in the ECHO PATHWAYS consortium of prospective pregnancy cohorts (GAPPS, CANDLE, TIDES). Women reported the duration of any and exclusive breastfeeding and child asthma outcomes during follow-up at child age 4 to 6 years. Outcomes included current wheeze (previous 12 months), ever asthma, current asthma (having ≥2 of current wheeze, ever asthma, medication use in past 12-24 months), and strict current asthma (ever asthma with either or both current wheeze and medication use in past 12-24 months). We used multivariable logistic regression to assess associations (odds ratios and 95% confidence intervals) between breastfeeding and asthma outcomes adjusting for potential confounders. We assessed effect modification by mode of delivery, infant sex, and maternal asthma.

RESULTS

Among women, 33%, 13%, 9%, and 45% reported 0 to less than 2, 2 to 4, 5 to 6, and more than 6 months of any breastfeeding, respectively. The duration of any breastfeeding had a protective linear trend with ever asthma but no other outcomes. There was a duration-dependent protective association of exclusive breastfeeding and child asthma outcomes (eg, current asthma adjusted odds ratio [95% confidence interval], 0.64 [0.41-1.02], 0.61 [0.38-0.98], and 0.52 (0.31-0.87) for 2to 4 months, 5 to 6 months, and more than 6 months, respectively, compared with <2 months). For exclusive breastfeeding, protective associations were stronger in dyads with children born by vaginal vs cesarean delivery although interactions did not reach statistical significance (Pinteractions 0.12-0.40).

CONCLUSION

Longer duration of exclusive breastfeeding had a protective association with child asthma.

Effect of Cold Storage on the Viable and Total Bacterial Populations in Human Milk

Expression and cold storage of human milk is a common practice. Current guidelines for cold storage of expressed milk do not take into account the impact on the milk microbiome. Here, we investigated the impact of cold storage on viable bacterial populations in human milk. Freshly expressed milk samples (n = 10) were collected and analysed immediately, stored at 4 °C for four days, −20 °C for 2.25 months and 6 months, and −80 °C for 6 months. Samples were analysed using propidium monoazide (PMA; a cell viability dye) coupled with full-length 16S rRNA gene. An aliquot of each sample was additionally analysed without PMA to assess the impact of cold storage on the total DNA profile of human milk. Cold storage significantly altered the composition of both the viable microbiome and total bacterial DNA profile, with differences in the relative abundance of several OTUs observed across each storage condition. However, cold storage did not affect the richness nor diversity of the samples (PERMANOVA all p > 0.2). Storage of human milk under typical and recommended conditions results in alterations to the profile of viable bacteria, with potential implications for infant gut colonisation and infant health.

Childhood eating practices are relevant to ultra-processed food consumption in adulthood: results from the Nutritionists' Health Study

Studies on childhood feeding and current food consumption, according to the NOVA classification, in adults are scarce. The objective of this study was to evaluate the relationship between childhood dietary practices and the current consumption of different categories of processed foods in young adults using data from the Nutritionists' Health Study (NutriHS) cohort. A cross-sectional analysis was performed using data of 392 on nutrition undergraduate students or nutritionists aged ≥18 years. Current food consumption was assessed using a food frequency questionnaire and the NOVA classification. The investigated childhood eating practices included fruit and vegetable intake, exclusive breastfeeding, and other breastfeeding practices. Participants breastfed with introduction of solid, semi-solid or soft foods before 6 months had higher current consumption of processed foods than those who were not breastfed (β = 4.30; 95% confidence interval [CI] = 0.56-8.04) and those who did not have the habits of eating fruits and vegetables during childhood consumed less unprocessed and minimally processed foods in adulthood than those who ate fruits and vegetables during infancy (β = -3.76; 95% CI = -0.82 to -6.70). Further, later introduction of infant formula or other types of milk between 3 and 5 months of age had a lower current consumption of ultra-processed foods than those fed infant formula or other types of milk before 1 month age of life (β = -3.09; 95% CI = -6.12 to -0.06). In conclusion, childhood feeding practices were linked to food consumption in adult life in NutriHS cohort, highlighting that the first 1000 days of life seems to impact on food choices during adulthood, with potential to protect against nutrition-related diseases later in life.

Association of Infant Feeding Methods and Excess Weight from Birth to Age 6

Objective: To examine the associations between human milk feeding method (at the breast versus bottle) and measures of child adiposity during the first 6 years of life. Study Design: Women 12 months' postpartum who delivered a singleton, liveborn infant at >24 weeks gestation completed a survey assessing infant feeding methods and sociodemographics. Mothers were recontacted when the child was 6 years old for a follow-up study assessing growth (N = 269). Children were categorized as ever or never having excess weight using weight-for-age z-scores (WAZ), weight-for-height z-scores (WHZ), and body mass index-for-age z-scores (BMIZ) from birth to 6 years. Modified Poisson regression estimated associations between the duration of each feeding method (exclusive and combined) with excess weight status. Mixed-effect models estimated associations between feeding methods and trajectories of the outcomes. Results: For all feeding practices, increasing duration (in months) was unassociated with the risk of ever having excess weight by age 6 years. Based on mixed models, longer duration of feeding human milk by any method was associated with lower BMIZ (adj β for 6-12 months versus 0-3 months = -0.50, 95% CI: -0.99 to -0.01) and also with the shape of the BMIZ trajectory curve. No other associations between feeding methods and excess weight outcomes were observed. Conclusions: Longer duration of feeding human milk was associated with lower average BMIZ in early childhood but feeding at the breast and feeding expressed milk were not clearly associated with the outcomes when considered separately. Larger studies would help clarify the associations between these specific feeding methods and outcomes. IRB17-00876.