Ashleigh H. Warden

Background: Sleep in early infancy supports neurodevelopment, yet the influence of breast milk composition on sleep duration remains unclear. Objective: To determine whether breast milk energy intake is associated with the duration and timing of subsequent infant sleep episodes. Methods: Thirty-four healthy, fully breastfeeding mother–infant dyads (infant age: 3.7 ± 1.3 months) recorded 24-h infant feeding and sleep data, with feed volumes measured by pre- and post-feed test-weighing. Milk samples were collected and analysed for macronutrient concentrations to calculate energy intake per feed. Linear mixed-effects models were used to examine whether energy intake from the preceding feed was associated with subsequent sleep duration. Additional models evaluated lagged and cumulative energy intake, and mixed-effects modelling was used for associations between feed energy and time until the next feed. Results: Intake for 24-h infant breast milk was 851.8 ± 194.2 mL and sleep duration was 15.5 ± 3.4 h. The mean energy density of the feeds was 674.7 ± 140.7 kcal/L. Energy intake for the breastfeed preceding a sleep episode was not associated with sleep duration (β = 4.13 min; 95% CI −0.89 to 9.15; p = 0.106). Energy intake from lagged feeds and cumulative energy intake across the three preceding breastfeeds were also not associated with sleep duration (p = 0.171 and p = 0.290 respectively) nor the time until the next breastfeed (β = −0.025; 95% CI −6.2 to 1.4; p = 0.212). Conclusions: In healthy breastfed infants, the energetic content of breast milk feeds was not associated with subsequent sleep duration or the time until the next feed. These findings suggest that infant sleep–wake behaviour and feeding patterns were not associated with short-term variation in breast milk energy intake. Other factors, including circadian and developmental processes, are likely to contribute to infant sleep behaviour.

Background/Objectives: Breast pumps are essential tools when breastfeeding dyads are separated or there are breastfeeding challenges that prevent or reduce effective milk removal. Hospital-grade and personal-use pumps offer different features and performance characteristics. Direct comparative studies evaluating pump efficacy and maternal satisfaction are limited in this area, hampering healthcare professionals in their support of lactating women. We compared the efficacy and maternal perceptions of a hospital-grade breast pump (Symphony; Medela AG) and an electric personal-use pump (Pump in Style Pro; Medela AG). Methods: In total, 28 lactating mothers with healthy-term infants participated in an unblinded randomised crossover trial. Participants attended two pumping sessions using either the hospital-grade pump or personal-use pump. Effectiveness of milk removal and maternal perception were measured. Participants completed a 24 h milk profile to enable calculation of the percentage of available milk removed from the breast. Results: There were no significant differences for milk removal efficacy parameters after accounting for pre-expression degree of fullness of the breast between pumps. Similarly, there was no difference in comfort ratings. However, mothers perceived the hospital-grade breast pump vacuum as smoother than the personal-use pump (p = 0.003) and rated the hospital-grade breast pump as having a more pleasant sound (p < 0.001). Both findings remained significant after adjustment for pre-expression degree of fullness (p < 0.001 and p = 0.030, respectively). Conclusions: The hospital-grade pump and the personal-use pump did not differ with respect to milk removal efficacy and comfort. However, participants did perceive differences in vacuum application.

Background: Whilst maternal body mass index (BMI) is linked to suboptimal breastfeeding outcomes, maternal body composition has not been assessed with respect to milk production (MP). Methods: Lactating mothers 1–6 months postpartum (n = 281) completed a demographic questionnaire and a 24 h MP measurement using the test-weigh method, enabling the calculation of 24 h MP parameters, breast storage capacity (BSC) and the percentage of available milk removed (PAMR). Body composition was measured with bioimpedance spectroscopy. Linear regression models were used to determine maternal and infant factors associated with MP parameters; structural equation modelling was used to assess the mediating role of BSC. Results: Higher maternal adiposity was associated with lower BSC (p ≤ 0.028), MP (p ≤ 0.003), infant breast milk intake (p ≤ 0.003) and total milk intake (p ≤ 0.026). Higher BSC was associated with higher MP (p < 0.001), with BSC confirmed as a mediator of the relationship between adiposity and MP (67.5%). Mean PAMR was negatively associated with BSC and milk removal frequency (both p < 0.001), and was lower in occasionally pumping compared to breastfeeding only (p = 0.037) and exclusively pumping mothers (p = 0.012). Conclusions: Our findings confirm maternal adiposity as a major contributor to low MP and reveal BSC, which is a measure of glandular tissue volume or breast development, as a mediator between adiposity and MP. This provides a rationale for antenatal lactation assessment of mothers and timely intervention in high-risk mothers to ensure they reach their full lactation potential.

Background/Objectives: Breastfeeding multiple birth infants (MBIs) poses unique challenges that require tailored support; however, research on these mothers’ experiences is limited. This study explored the breastfeeding journeys of Australian mothers of MBIs, highlighting barriers, facilitators, and support needs. Methods: Data were collected via an online survey (May–August 2024) and included quantitative data on breastfeeding initiation, duration, and challenges, as well as qualitative insights into mothers’ experiences. Thematic analysis was used to identify key themes, and statistical analyses were used to compare breastfeeding outcomes by parity. Results: While most mothers (87%) had an antenatal intention to breastfeed, they faced barriers such as latching difficulties (56%), inadequate milk supply (49%), and sore nipples (47%). Preterm births (58%) and neonatal unit admissions delayed the breastfeeding initiation. Most mothers (99%) used electric breast pumps to boost milk supply (68%) and enable expressed breast milk feeding by other caregivers (65% of mothers). While 72% were satisfied with hospital breastfeeding support and some mothers received excellent hands-on support, others felt neglected due to busy staff or conflicting advice. Mothers frequently reported that breastfeeding guidance was geared toward singletons, leaving them unprepared for the challenges of feeding multiples. Mothers’ suggestions for improving care included specialised guidance, better access to lactation support, and in-home practical support to alleviate the burden of feeding and expressing. Additionally, mothers reported that healthcare professionals should be trained to offer practical, non-judgemental support to help mothers navigate the elaborate challenges of breastfeeding MBIs. Conclusions: This study underscores the need for early postpartum support and tailored guidelines to enhance MBI breastfeeding outcomes and maternal-infant well-being.

Background/Objectives: Optimal infant growth is reliant on the sufficient intake of human milk. Studies in animal models speculate that multiparous mothers produce a higher milk yield compared to primiparous mothers. We aimed to examine if there are relationships between consecutive lactations and infant demographics and both maternal 24 h milk production (MP) and infant milk intake (MI). Methods: Lactating mothers 1–6 months postpartum (n = 36; 25 fully breastfeeding (FBF), 11 supplementing with commercial milk formula (partly breastfeeding (PBF)) test-weighed their infants for 24 h during two consecutive lactations and provided demographic information. Twenty-four-hour MP by breast, infant MI (including mothers’ own expressed milk and formula), breastfeeding and expressing frequencies were measured. The statistical analysis used linear mixed modelling accounting for infant birth weight (FBF) or time postpartum (PBF) and for the random effect of the participant. Results: In the FBF group, there were no differences between lactations in terms of MP (p = 0.31) or the infant mother’s own MI (p = 0.14). The birth weight was higher for consecutive lactation infants (p = 0.008). Infant sex was not associated with MP (p = 0.12) or the infant mother’s own MI (p = 0.090). In the PBF group, the breastfeeding frequency (p = 0.042), MP (p = 0.025) and infant mother’s own MI (p = 0.019) were higher in consecutive lactations whilst formula intake was lower (p = 0.004). Conclusions: This study suggests that in fully breastfeeding women, there is no significant effect of consecutive lactation or infant sex on MP or infant MI during established lactation.

Human milk is a complex biofluid containing a diverse array of cells crucial for infant health. Despite their importance, our understanding of these cells remains incomplete due to technical challenges. To fully comprehend human milk cells, high-resolution imaging technologies that can directly measure biological processes are required. We have developed a specialized imaging platform combining light and electron microscopy for human milk cell imaging. To identify different cell types, human milk cells were first stained with several specific cell markers (e.g., EpCAM and MUC1 for lactocytes, CD16 and CD66b for neutrophils, and HLA-DR and CD68 for macrophages) prior to light (confocal) microscopy. Following this, the same cells were processed with osmium staining, resin embedding, and sectioning for electron microscopy, allowing us to observe ultrastructural details. Our imaging workflow has enabled nanoscale visualization of human milk cells, resulting in a first-of-its-kind comprehensive database profiling the organelle-level ultrastructure of different cell types present in human milk. The cells in the human milk are highly heterogenous, featuring a large proportion of lactocytes and lipid droplets, binucleated lactocytes, neutrophil aggregation, neutrophil extracellular traps, dendritic cells/macrophages with bacteria, and immunophagocytosis. This study provides valuable cellular insights contributing to a deeper understanding of human milk biology.

Background: Whilst it is inconvenient and time-intensive, predominantly (PP) and exclusively pumping (EP) mothers rely on breast expression to provide milk for their infants and to ensure continued milk supply, yet these populations are poorly understood. Methods: We assessed and characterised Western Australian PP mothers (n = 93) regarding 24 h milk production (MP) and infant milk intake and demographics, perinatal complications and breastfeeding difficulties, the frequencies of which were compared with published general population frequencies. Pumping efficacy and milk flow parameters during a pumping session in PP mothers (n = 32) were compared with those that pump occasionally (reference group, n = 60). Results: PP mothers had a higher frequency of pregnancy complications and breastfeeding difficulties than the general population. Exclusive pumping did not impact the 24 h MP and the amount of milk available to the infant. PP mothers had more milk ejections, longer active flow duration and lower milk removal efficacy ratios; however, responsiveness to pump (time to first milk ejection), total flow duration, time to stop pumping, percentage of available milk removed and comfort parameters were not different to the reference group. Conclusions: Despite the reported challenges, when an effective pump is used, predominant or exclusive pumping does not negatively affect the 24 h MP and the amount of milk available to the infant. Increasing awareness of the impacts of perinatal and breastfeeding complications on women may assist health professionals in early identification of mothers at high risk for early cessation of breastfeeding, escalating early postpartum intervention and targeted breastfeeding support.

While the health advantages of postpartum physical activity are clear, fewer than 25% of Australian women engage in physical activity in the year after giving birth. Physical activity may promote weight loss and a healthier body composition in the months after birth; however, evidence of this is limited. An understanding of identified facilitators and barriers to postpartum physical activity and knowledge of changes in body composition after birth will assist healthcare providers in guiding women on their return to physical activity. The primary aim of this study was to examine Australian women’s identified facilitators and barriers to physical activity in the first 12 months postpartum. The secondary aim was to investigate maternal body composition changes between 6–8 weeks and 3–3.5 months postpartum. This study comprised an anonymous online mixed-methods questionnaire and a body composition sub-study. Participants completed an anonymous questionnaire about their pregnancy and birth and their physical activity before and during pregnancy and after birth. Qualitative responses to questions about facilitators and barriers to postpartum physical activity were analysed using content analysis. Sub-study: Women that had given birth within the last 6 weeks were invited to attend study sessions at 6–8 weeks postpartum and then 6 weeks later (3–3.5 months) for anthropometric (weight, height, BMI) and body composition measurements (fat mass, fat-free mass) using a bioelectrical impedance analyser ImpediMed SFB7 (ImpediMed, Brisbane, Queensland, Australia). Participation in physical activity in the previous 7 days and the infant feeding method were recorded at each visit. Survey data of n = 469 women were available for analysis. Content analysis of the qualitative data identified the main barriers to physical activity as infant care, timing, and physical limitations. Most survey participants (72%) were active at the time of participation, yet only 23% (n = 110) met the postpartum exercise recommendations of 150 minutes/week. The sub-study involving 30 women showed no significant changes in weight (p = 0.46), BMI (p = 0.45), fat mass (p = 0.36), or fat-free mass (p = 0.23) between 6–8 weeks and 3–3.5 months postpartum. When compared by breastfeeding status, partially breastfeeding women had a larger magnitude of change in weight (−1.15 ± 1.6 vs. 0.24 ± 1.3 kg, respectively, p = 0.015) and BMI (−0.43 ± 0.62 vs. 0.09 ± 0.50 kg/m², respectively, p = 0.016) than fully breastfeeding women, which may be partly explained by the fat-free mass increase in the latter group (−0.19 ± 2.4 vs. 2.67 ± 5.7 kg, respectively, p = 0.089). At 6–8 weeks postpartum, 45% of participants (n = 14) engaged in at least 150 minutes/week of exercise, with no significant differences in changes in maternal body composition at 3–3.5 months between those meeting the recommendations and those who were not. These findings provide valuable insights that can inform the guidance, support, and education of postpartum women when planning their return to physical activity and form the basis of future studies of exercise and body composition changes in breastfeeding women.

The Breastfeeding Longitudinal Observational Study of Mothers and kids (BLOSOM) is a single-centre prospective cohort study conducted in Perth (Western Australia) that collected data from 2018 to 2020 and aimed to investigate the mechanisms by which human milk affects infant growth, health, and body composition

Despite the available evidence, mothers often do not tailor the duration of their pumping sessions to their individual milk flow pattern