This study aimed to investigate relationships between infant abdominal visceral and subcutaneous adiposity and human milk (HM) components and maternal body composition (BC) during first year of lactation. Subcutaneous-abdominal depth (SAD), subcutaneous-abdominal fat area (SFA), visceral depth (VD) and preperitoneal fat area of 20 breastfed infants were assessed at 2, 5, 9 and 12 months using ultrasound. Maternal BC was determined with bioimpedance spectroscopy. HM macronutrients and bioactive components concentrations and infant 24-h milk intake were measured and calculated daily intakes (CDI) determined. Maternal adiposity associated with infant SFA (negatively at 2, 5, 12, positively at 9 months, all overall p < 0.05). 24-h milk intake positively associated with infant SAD (p = 0.007) and VD (p = 0.013). CDI of total protein (p = 0.013), total carbohydrates (p = 0.004) and lactose (p = 0.013) positively associated with SFA. Lactoferrin concentration associated with infant VD (negatively at 2, 12, positively at 5, 9 months, overall p = 0.003). CDI of HM components and maternal adiposity have differential effects on development of infant visceral and subcutaneous abdominal adiposity. Maintaining healthy maternal BC and continuing breastfeeding to 12 months and beyond may facilitate favourable BC development reducing risk of obesity.

Researchers have recently called for human lactation research to be conceptualized as a biological framework where maternal and infant factors impacting human milk, in terms of composition, volume and energy content are studied along with relationships to infant growth, development and health. This approach allows for the development of evidence-based interventions that are more likely to support breastfeeding and lactation in pursuit of global breastfeeding goals. Here we summarize the seminal findings of our research programme using a biological systems approach traversing breast anatomy, milk secretion, physiology of milk removal with respect to breastfeeding and expression, milk composition and infant intake, and infant gastric emptying, culminating in the exploration of relationships with infant growth, development of body composition, and health. This approach has allowed the translation of the findings with respect to education, and clinical practice. It also sets a foundation for improved study design for future investigations in human lactation.

Background Health professionals caring for women and infants experiencing difficulty with breastfeeding have reported deficiencies in evidence-based lactation knowledge. LactaMap is an online lactation care support system with more than 100 clinical practice guidelines to support breastfeeding care. Clinical practice guidelines support medical decision-making by summarising scientific evidence into systematically developed statements for specific clinical circumstances. Both common-sense and theory-based approaches have been used for guideline development and debate continues regarding which is superior. LactaMap clinical practice guidelines were created over the course of 5 years using a common-sense approach that was refined inductively. The aim of this study was to incorporate a theory-based framework approach into the methodology for ongoing update and review of LactaMap clinical practice guidelines. Methods The Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument was chosen as the framework-based approach to appraise LactaMap guideline quality. The study was conducted in two phases. The first phase appraised all 103 original LactaMap guidelines. The second phase appraised a subset of 15 updated LactaMap guidelines using improved methodology guided by phase 1, as well as 15 corresponding original (un-updated) guidelines. Results Mean Domain scores for 103 LactaMap original guidelines were above 75% in 3 of the 6 AGREE II quality Domains and no mean Domain score rated poorly. Update of guideline methodology was guided by phase 1 appraisals. Improved documentation of methods relating to questions in the Rigour of Development Domain resulted in improvement in mean Domain score from 39 to 72%. Conclusions This study showed that a theory-based approach to guideline development methodology can be readily integrated with a common-sense approach. Factors identified by AGREE II theory-based framework provided practical guidance for changes in methodology that were integrated prior to LactaMap website publication. Demonstration of high quality in LactaMap clinical practice guideline methodology ensures clinicians and the public can have trust that the content founded on them is robust, scientific and of highest possible quality.

During the last decade, there have been several publications highlighting the need for consistent terminology in breastfeeding research. Standard terms and definitions are essential for the comparison and interpretation of scientific studies that, in turn, support evidence-based education, consistency of health care, and breastfeeding policy. Inconsistent advice is commonly reported by mothers to contribute to early weaning. A standard language is the fundamental starting point required for the provision of consistent advice. LactaPedia () is a comprehensive lactation glossary of over 500 terms and definitions created during the development of LactaMap (), an online lactation care support system. This paper describes the development of LactaPedia, a website that is accessible free of charge to anyone with access to the Internet. Multiple methodological frameworks were incorporated in LactaPedia's development in order to meet the needs of a glossary to support both consistent health care and scientific research. The resulting LactaPedia methodology is a six-stage process that was developed inductively and includes framework to guide vetting and extension of its content using public feedback via discussion forums. The discussion forums support ongoing usability and refinement of the glossary. The development of LactaPedia provides a fundamental first step towards improving breastfeeding outcomes that are currently well below World Health Organisation recommendations globally.

Background To investigate relationships between infant body composition (BC) and human milk (HM) immunomodulatory proteins (IMPs) during the first 12 months of lactation. Methods BC of breastfeeding dyads (n = 20) was measured with ultrasound skinfolds (infants) and bioimpedance spectroscopy (infants/mothers) at 2, 5, 9, and/or 12 months post partum. Breastfeeding frequency, 24-h milk intake, and IMP concentrations (lactoferrin, lysozyme, secretory immunoglobulin A (sIgA)) were measured, and calculated daily intakes (CDIs) were determined. We used linear regression/mixed-effects models and adjusted results for multiple comparisons. Results No associations were seen between maternal characteristics and IMP concentrations/CDIs or between IMP concentrations and infant BC. Lactoferrin CDI was negatively associated with infant fat-free mass index (P = 0.002); lysozyme CDI was positively associated with infant fat mass (P = 0.004) and fat mass index (P = 0.004) measured with ultrasound skinfolds. Conclusion In this small cohort of infants breastfed on demand during first year of life, we report differential associations of HM IMPs with infant BC, showing that in addition to their critical role in shaping infant immunity, lactoferrin, and lysozyme also influence development of infant BC, highlighting the importance of breastfeeding for 12 months and beyond. Impact HM IMPs (concentrations and, most importantly, daily intakes) time-dependently and differentially associate with development of infant lean mass and adiposity during first 12 months of lactation. There is no information on how intakes and concentrations of these components affect development of infant BC. HM contains IMPs-lactoferrin, lysozyme, and sIgA, which not only play a critical role in shaping infant's immunity, but also influence infant growth and development of BC, highlighting the importance of breastfeeding for 12 months and beyond and warranting careful consideration of the dose effects of supplemented formula.

AimTo determine the impact of the pumping regimes of women with preterm infants on the daily milk production, and on the short-term rate of milk synthesis during early lactation to support evidence-based recommendations for optimising milk production.MethodsMothers of preterm infants (n=25) recorded start time, finish time and expression volumes from every breast expression on days 10, 15–20 postpartum.ResultsExpressing more often than five times per day did not result in a significant increase in daily milk production. Milk volume per expression per breast increased for intervals between expressions of between 2and6 hours then reached a plateau when the interval between expression was 7 hours or longer. The short-term rate of milk synthesis decreased as the interval between expressions increased until about 7.5 hours at which point it begun to increase (p value associated with interval between expressions^2<0.001).ConclusionThe strong inverse association between the short-term rate of milk synthesis and the interval between expressions for intervals up to 7 hours suggest that the maximum interval between expressions should be 7 hours. Data suggest that, on average, the mothers should express at least five times a day to maximise daily milk production. Considering inter-individual variation, determination of an individual mother’s maximum interval between expressions that does not compromise the short-term rate of milk synthesis will help to optimise daily milk production while minimising the demands on the mother’s time.

Human milk (HM) carbohydrates may affect infant appetite regulation, breastfeeding patterns, and body composition (BC). We investigated relationships between concentrations/calculated daily intakes (CDI) of HM carbohydrates in first year postpartum and maternal/term infant BC, as well as breastfeeding parameters. BC of dyads (n = 20) was determined at 2, 5, 9, and/or 12 months postpartum using ultrasound skinfolds (infants) and bioelectrical impedance spectroscopy (infants/mothers). Breastfeeding frequency, 24-h milk intake and total carbohydrates (TCH) and lactose were measured to calculate HM oligosaccharides (HMO) concentration and CDI of carbohydrates. Statistical analysis used linear regression/mixed effects models; results were adjusted for multiple comparisons. Higher TCH concentrations were associated with greater infant length, weight, fat-free mass (FFM), and FFM index (FFMI), and decreased fat mass (FM), FM index (FMI), %FM and FM/FFM ratio. Higher HMO concentrations were associated with greater infant FFM and FFMI, and decreased FMI, %FM, and FM/FFM ratio. Higher TCH CDI were associated with greater FM, FMI, %FM, and FM/FFM ratio, and decreased infant FFMI. Higher lactose CDI were associated with greater FM, FMI, %FM, and FM/FFM, ratio and decreased FFMI. Concentrations and intakes of HM carbohydrates differentially influence development of infant BC in the first 12 months postpartum, and may potentially influence risk of later obesity via modulation of BC.

INTRODUCTION Lactogenesis II (LaII) failure can be prevented in at-risk mothers with simple proactive interventions. In a randomised trial, we investigated the efficacy of early and regular breast milk expression in establishing LaII, using an electric double-breast pump. METHODS Mothers with uncomplicated singleton deliveries were randomised to intervention (n = 31) or control (n = 29) groups. The former commenced breast milk expression with an electric pump within one hour of delivery and maintained regular expression with direct breastfeeding. Control mothers directly breastfed without regular pump expression. Expressed milk volumes were analysed for citrate, lactose, sodium and protein. RESULTS Median time of LaII was Day 3 (interquartile range [IQR] 1 day) with intervention and on Day 4 (IQR 1 day) among controls (p = 0.03). Biochemical steady-state concentrations were achieved around early Day 4 (sodium, total protein) and Days 4-5 (citrate, lactose). Sodium, protein and lactose levels were similar in both groups over seven days, at 5.80 mM, 0.68 mM and -13.38 mM, respectively. Mean daily milk volume with intervention was 73.9 mL on Day 3 and 225.2 mL on Day 7, greater than controls (25.4 mL on Day 3 and 69.2 mL on Day 7; p < 0.2). Mean infant weights were similar on Day 8 at 3,477 g with intervention and 3,479 g among controls. CONCLUSION LaII is established by postnatal Day 3 with early initiation of regular breast milk expression, a useful intervention for mothers at risk of early-onset breastfeeding failure.

With the exception of infant growth, there are no well-defined parameters describing normal human lactation. This represents a major gap in the continuum of care that does not exist for other major organs. Biological normality occurs naturally and is characterized by well-integrated function. We have proposed a definition that highlights four key elements that describe parameters for biological normality: comfort, milk supply, infant health, and maternal health. Notwithstanding the current limitations, published data have been collated to provide preliminary markers for the initiation of lactation and to describe objective tests once lactation is established. Reference limits have been calculated for maternal markers of secretory activation, including progesterone in maternal blood and total protein, lactose, sodium, and citrate in maternal milk. Objective measurements for established lactation, including 3-hourly pumping and 24-hour milk production, together with pre-feed to post-feed milk fat changes (a useful indicator of the available milk removed by the infant) have been outlined. Considered together with the parameters describing normal function, this information provides a preliminary objective framework for the assessment of human lactation.

With the exception of infant growth, there are no well-defined parameters describing normal human lactation. This represents a major gap in the continuum of care that does not exist for other major organs. Biological normality occurs naturally and is characterized by well-integrated function. We have proposed a definition that highlights four key elements that describe parameters for biological normality: comfort, milk supply, infant health, and maternal health. Notwithstanding the current limitations, published data have been collated to provide preliminary markers for the initiation of lactation and to describe objective tests once lactation is established. Reference limits have been calculated for maternal markers of secretory activation, including progesterone in maternal blood and total protein, lactose, sodium, and citrate in maternal milk. Objective measurements for established lactation, including 3-hourly pumping and 24-hour milk production, together with pre-feed to post-feed milk fat changes (a useful indicator of the available milk removed by the infant) have been outlined. Considered together with the parameters describing normal function, this information provides a preliminary objective framework for the assessment of human lactation.

Breastfeeding has been implicated in the establishment of infant appetite regulation, feeding patterns and body composition (BC). A holistic approach is required to elucidate relationships between infant and maternal BC and contributing factors, such as breastfeeding parameters. Associations between maternal and breastfed term infant BC (n = 20) and feeding parameters during first 12 months of lactation were investigated. BC was measured at 2, 5, 9 and/or 12 months postpartum with ultrasound skinfolds (US; infants only) and bioimpedance spectroscopy (infants and mothers). 24-h milk intake (MI) and feeding frequency (FFQ) were measured. Higher FFQ was associated with larger 24-h MI (p ≤ 0.003). Higher 24-h MI was associated with larger infant fat mass (FM) (US: p ≤ 0.002), greater percentage FM (US: p ≤ 0.008), greater FM index (FMI) (US: p ≤ 0.001) and lower fat-free mass index (FFMI) (US: p = 0.015). Lower FFQ was associated with both larger FFM (US: p ≤ 0.001) and FFMI (US: p < 0.001). Greater maternal adiposity was associated with smaller infant FFM measured with US (BMI: p < 0.010; %FM: p = 0.004; FMI: p < 0.011). Maternal BC was not associated with FFQ or 24-h MI. These results reinforce that early life is a critical window for infant programming and that breastfeeding may influence risk of later disease via modulation of BC.

Human milk (HM) influences infant feeding patterns and body composition (BC). This small proof-of concept longitudinal study investigated relationships between infant/maternal BC and HM casein, whey and total protein during the first 12 months of lactation. BC of breastfeeding dyads (n = 20) was measured at 2 (n = 15), 5 (n = 20), 9 (n = 19), and/or 12 (n = 18) months postpartum with ultrasound skinfolds (infants) and bioimpedance spectroscopy (infants/mothers). Proteins concentrations and 24-h milk intake were measured and calculated daily intakes (CDI) determined. Higher maternal weight, body mass index, fat-free mass, fat-free mass index, and fat mass index were associated with higher concentration of whey protein (p ≤ 0.034, n = 20). There were no associations between infant BC and concentrations of all proteins, and CDI of whey and total protein. Higher CDI of casein were associated with lower infant fat-free mass (p = 0.003, n = 18) and higher fat mass (p < 0.001), fat mass index (p = 0.001, n = 18), and % fat mass (p < 0.001, n = 18) measured with ultrasound skinfolds. These results show a differential effect of HM casein on development of infant BC during the first year of life, suggesting that there is a potential to improve outcome for the infant through interventions, such as continuation of breastfeeding during the first 12 months of life and beyond, which may facilitate favourable developmental programming that could reduce risk of non-communicable diseases later in life.