Exclusive breastfeeding duration and cardiorespiratory fitness in children and adolescents

Breastfeeding, Walking Onset, and Abdominal Obesity Are Determinants of Physical Fitness among Latin American and Spanish Schoolchildren: A Cross-Cultural Study

OBJECTIVE

To comp+are levels of physical fitness between Ecuador and Spain and identify whether breastfeeding period, walking onset, and abdominal obesity are determinants of physical performance in schoolchildren from Ecuador and Spain.

METHODS

a total of 352 schoolchildren (6-12 years old) from Ecuador (n = 176) and Spain (n = 176) joined in this study. Anthropometric measures, socio-demographic characteristics, and physical fitness were evaluated.

RESULTS

Spanish schoolchildren showed better performance in handgrip strength, standing long jump, and 25 m sprint (p = 0.021; p < 0.001; p < 0.001; p < 0.001, respectively). Furthermore, Spanish children showed better cardiorespiratory fitness (p < 0.001) and a higher VO2 max (p = 0.002) with regards to their peers. In addition, children from Ecuador and Spain showed an influence of breastfeeding period (p ranged from <0.001 to 0.043) and walking onset (p ranged from <0.001 to 0.032) on physical performance. Moreover, physical fitness components were protective factors of abdominal obesity in Ecuadorian and Spanish schoolchildren (p ranged from =0.001 to 0.049).

CONCLUSIONS

Our findings revealed the influence of the infancy period and the onset of walking on children's physical performance, highlighting the importance of these factors in motor development during early childhood and also their influence in middle childhood and throughout adulthood.

Offspring sex modifies the association between early-pregnancy adiposity and 2-year-old physical activity-The Glowing Study

BACKGROUND

Rodent models suggest that in utero exposure to under and overnutrition programs offspring physical activity (PA) behaviors. Such nexus has not been established in humans. This study evaluated the association of early pregnancy maternal adiposity with offspring PA at age 2 years (2-yo-PA) taking into consideration prenatal and postnatal factors.

METHODS

Women (n = 153) were enrolled early in pregnancy (<10 weeks). At enrollment, maternal adiposity [air displacement plethysmography, fat mass index (FMI, kg/m2)] and PA (accelerometers, activity counts) were measured, and age, race, and education self-reported. Gestational weight gain was measured at the research facility. Offspring birthweight and sex were self-reported. At age 2 years, parental feeding practices (child feeding questionnaire) were assessed, whereas anthropometrics (length and weight) and physical activity (accelerometers) were objectively measured. Offspring body mass index z-scores were calculated. Generalized linear regression analysis modeled the association of maternal FMI and 2-yo-PA [average activity counts (AC)4/day].

RESULTS

In bivariate associations, 2-yo-PA did not associate with maternal FMI (β = -0.22, CI = -0.73 to 0.29, p = 0.398). However, maternal FMI interacted with offspring sex in association with 2-yo-PA. Specifically, 2-yo-PA was lower in girls (β = -1.14, CI = -2.1 to -0.18, p = 0.02) compared to boys when maternal FMI was ≥7 kg/m2. When stratified by sex, 2-yo-PA of girls negatively associated with maternal FMI (β = -0.82, CI = -1.43 to 0.29, p = 0.009) while no association was found between maternal FMI and boy's PA (β = 0.32, CI = -0.38 to 1.01, p = 0.376).

CONCLUSIONS

The association of 2-yo-PA and early pregnancy maternal adiposity was modified by offspring sex. Offspring's physical activity decreased with increasing early pregnancy adiposity maternal in girls but not boys in second parity dyads.

Birth-related and current factors associated with physical inactivity in the leisure time in Brazilian adolescents

Background

To determine whether biological and sociodemographic factors at birth and current factors are associated with insufficient physical activity during leisure among Brazilian adolescents.

Methods

A school-based cross-sectional study with national coverage was conducted involving Brazilian adolescents 12 to 17 years of age in municipalities with more than 100 thousand residents. The sample consisted of 74,589 adolescents who participated in the Study of Cardiovascular Risk in Adolescents. Insufficient leisure-time physical activity was categorized based on total volume (<300 minutes/week = insufficiently active; >300 minutes/week = sufficiently active). Poisson regression models were used to assess associated factors.

Results

Most adolescents were classified as insufficiently active (54.8%; 95%CI: 53.7–55.9). The variables associated with insufficient physical activity during leisure were the female sex (70.4%; 95%CI: 68.8–71.9), age between 15 and 17 years (57.8%; 95%CI: 56.3–59.2), pertaining to the low or middle class (54.5%; 95%CI: 52.8–56.1), and not being overweight (55.9%; 95%CI: 54.6–57.1).

Conclusion

Contrary to our hypothesis, birth related factors (e.g., low birth weight, preterm birth and exclusive breastfeeding until 6 months of age) are not associated with physical inactivity. The prevalence of insufficient physical activity during leisure was high among the adolescents evaluated and was associated with sociodemographic characteristics as well as nutritional status. It is necessary to implement strategies focused on physical activity at schools.

Immunomodulatory Properties of Human Breast Milk: MicroRNA Contents and Potential Epigenetic Effects

Infants who are exclusively breastfed in the first six months of age receive adequate nutrients, achieving optimal immune protection and growth. In addition to the known nutritional components of human breast milk (HBM), i.e., water, carbohydrates, fats and proteins, it is also a rich source of microRNAs, which impact epigenetic mechanisms. This comprehensive work presents an up-to-date overview of the immunomodulatory constituents of HBM, highlighting its content of circulating microRNAs. The epigenetic effects of HBM are discussed, especially those regulated by miRNAs. HBM contains more than 1400 microRNAs. The majority of these microRNAs originate from the lactating gland and are based on the remodeling of cells in the gland during breastfeeding. These miRNAs can affect epigenetic patterns by several mechanisms, including DNA methylation, histone modifications and RNA regulation, which could ultimately result in alterations in gene expressions. Therefore, the unique microRNA profile of HBM, including exosomal microRNAs, is implicated in the regulation of the genes responsible for a variety of immunological and physiological functions, such as FTO, INS, IGF1, NRF2, GLUT1 and FOXP3 genes. Hence, studying the HBM miRNA composition is important for improving the nutritional approaches for pregnancy and infant's early life and preventing diseases that could occur in the future. Interestingly, the composition of miRNAs in HBM is affected by multiple factors, including diet, environmental and genetic factors.

Associations of Infant Feeding with Body Composition and Cardiometabolic Health in Young Female University Students

Background:

We assessed the association of infant feeding with body composition and cardiometabolic health at 20 years in a setting where infant feeding is not associated with socioeconomic status.

Materials and methods:

Body size trajectory since birth, current body composition measured using whole-body dual-energy X-ray absorptiometry, and a broad range of cardiometabolic risk factors were compared cross-sectionally among young female university students who were ever breastfed (n = 158, 120 exclusively, and 38 mainly), mixed fed (n = 124), and formula fed (n = 15, 10 mainly, and 5 exclusively)

Results:

Compared with breastfed and mixed fed women, formula fed women had higher serum total and low-density lipoprotein (LDL) cholesterol although fat mass, fat distribution, fasting glucose, and insulin and high-density lipoprotein cholesterol did not differ. In addition, resting heart rates were higher in formula fed women compared with the other two groups of women although systolic and diastolic blood pressure did not differ. Further, formula fed women had higher adiponectin while serum leptin did not differ. There was no difference in birthweight, weight and height in childhood and adolescence, and glucose tolerance. On multivariate logistic regression analysis, formula feeding was associated with resting heart rates (odds ratio [OR]: 1.06, confidence interval [95% CI]; 1.01–1.12, p = 0.01) and adiponectin (OR: 1.3, 95% CI; 1.1–1.5, p < 0.001) independently of serum total and LDL cholesterol.

Conclusions:

Breastfeeding may be associated with favorable lipid profile and autonomic nervous function in young adults through mechanisms unrelated to adiposity, implicating potential long-term benefits of breastfeeding for cardiovascular health. Higher adiponectin in nonbreastfed women warrants further studies.

Early life factors and white matter microstructure in children with overweight and obesity: The ActiveBrains project

BACKGROUND & AIMS

Exposure to a suboptimal environment during the fetal and early infancy period's results in long-term consequences for brain morphology and function. We investigated the associations of early life factors such as anthropometric neonatal data (i.e., birth length, birth weight and birth head circumference) and breastfeeding practices (i.e., exclusive and any breastfeeding) with white matter (WM) microstructure, and ii) we tested whether WM tracts related to early life factors are associated with academic performance in children with overweight/obesity.

METHODS

96 overweight/obese children (10.03 ± 1.16 years; 38.7% girls) were included from the ActiveBrains Project. WM microstructure indicators used were fractional anisotropy (FA) and mean diffusivity (MD), derived from Diffusion Tensor Imaging. Academic performance was evaluated with the Battery III Woodcock-Muñoz Tests of Achievement. Regression models were used to examine the associations of the early life factors with tract-specific FA and MD, as well as its association with academic performance.

RESULTS

Head circumference at birth was positively associated with FA of the inferior fronto-occipital fasciculus tract (0.441; p = 0.005), as well as negatively associated with MD of the cingulate gyrus part of cingulum (-0.470; p = 0.006), corticospinal (-0.457; p = 0.005) and superior thalamic radiation tract (-0.476; p = 0.001). Association of birth weight, birth length and exclusive breastfeeding with WM microstructure did not remain significant after false discovery rate correction. None tract related to birth head circumference was associated with academic performance (all p > 0.05).

CONCLUSIONS

Our results highlighted the importance of the perinatal growth in WM microstructure later in life, although its possible academic implications remain inconclusive.

Predictors of cardiovascular health in teenagers (aged 13-14 years): a cross-sectional study linked with routine data

Objective

To examine the predictors of cardiovascular health in teenagers (aged 13-14 years).

Methods

Measures of arterial stiffness (augmentation index (AIx)), blood pressure and cardiovascular fitness were taken from 234 teenage children (n=152 boys) and subsequently linked to routine data (birth and general practice records, education data and hospital admission data). Deprivation at school and at individual level was measured at birth, at 1 year old, at 13 years old and at secondary school using the Welsh Index of Multiple Deprivation. Multivariate regression analysis determined associations between routinely collected data and cardiovascular measures.

Results

Teenagers had higher AIx (2.41 (95% CI 1.10 to 3.72)), ran fewer metres (-130.08 m (95% CI -234.35 to -25.78)) in the Cooper Run Test if they attended a more deprived school. However, higher individual level deprivation was associated with greater fitness (199.38 m (95% CI 83.90 to 314.84)). Higher systolic blood pressure was observed in first born children (10.23 mm Hg (95% CI 1.58 to 18.88)) and in those who were never breastfed (4.77 mm Hg (95% CI 1.10 to 8.42)).

Conclusions

Improving heart health in deprived areas requires multilevel action across childhood namely, active play and programmes that promote physical activity and fitness and, the promotion of breastfeeding. Recognition of the important early indicators and determinants of cardiovascular health supports further development of the evidence base to encourage policy-makers to implement preventative measures in young people.

Association of Breastfeeding Duration with Susceptibility to Allergy, Influenza, and Methylation Status of TLR1 Gene

Background and Objectives: This study aimed to investigate the possible association between exclusive breastfeeding duration during early infancy and susceptibility to allergy and influenza in adulthood. Furthermore, we also investigated the association of breastfeeding duration with DNA methylation at two sites in the promoter of the toll-like receptor-1 (TLR1) gene, as well as the association between DNA methylation of the toll-like receptor-1 (TLR1) gene and susceptibility to different diseases. Materials and Methods: Blood samples were collected from 100 adults and classified into two groups according to breastfeeding duration (<6 months and ≥6 months) during infancy. Subjects were asked to complete a questionnaire on their susceptibilities to different diseases and sign a consent form separately. Fifty-three samples underwent DNA extraction, and the DNA samples were divided into two aliquots, one of which was treated with bisulfite reagent. The promoter region of the TLR1 gene was then amplified by polymerase chain reaction (PCR) and sequenced. Results: We found a significant association between increased breastfeeding duration and a reduction in susceptibility to influenza and allergy, as well asa significant reduction in DNA methylation within the promoter of the TLR1 gene. No association was found between DNA methylation and susceptibility to different diseases. Conclusions: The findings demonstrate the significance of increased breastfeeding duration for improved health outcomes at the gene level.

Exclusive Breastfeeding Is Favorably Associated with Physical Fitness in Children

Objective: To examine the potential association between exclusive breastfeeding and its duration on physical fitness (PF) components during childhood. Materials and Methods: A random sample of 5,125 dyads children and their mothers was evaluated. With the use of a standardized questionnaire, telephone interviews were carried out for the collection of maternal lifestyle factors (e.g., breastfeeding and its duration, etc.). Data from five PF tests (e.g., vertical jump, standing long jump, small ball throw, 30-m sprint, and 20-m shuttle run) were used to assess lower and upper body strength, speed, and cardiorespiratory fitness (CRF). Linear and logistic regression models were estimated and adjusted for children's body mass index (BMI) and birth weight, and parental factors (prepregnancy BMI, gestational weight gain, gestational age, pregnancy in vitro, parity before, and educational level). Results: Among boys, exclusive breastfeeding was favorably associated with CRF (b = 0.07), lower body strength (b = 0.41), upper body strength (b = 0.10), and speed (b = -0.11). Also, among girls, we found a favorable association between exclusive breastfeeding and CRF (b = 0.07), lower body strength (b = 0.47), upper body strength (b = 0.10), and speed (b = -0.11). All of the associations remained significant after adjusting for several potential confounders. With the exception of speed test in girls, children who were exclusively breastfed ≥6 months had 10-40% increased odds for average/high performances in PF tests in comparison with those who were breastfed <1 month. Conclusions: Exclusive breastfeeding ≥6 months had a favorable influence on PF test performances in childhood. It seems that exclusive breastfeeding could play a significant role in children's future health.

Relationship between exclusive breast feeding and cardiorespiratory fitness in children and adolescents: a protocol for a systematic review and meta-analysis

INTRODUCTION

Breast feeding has been considered important due to its short-term and long-term benefits on infant and maternal health. Regarding the long-term benefits, the influence of exclusive breastfeeding on cardiorespiratory fitness (CRF) during childhood and adolescence has been studied, although with controversial conclusions. This study protocol aims to provide a clear and standardised procedure for systematically reviewing the relationship between breast feeding, in terms of duration and exclusivity, and CRF in children and adolescents.

METHODS AND ANALYSIS

This systematic review and meta-analysis protocol is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. A literature search will be conducted in MEDLINE, EMBASE, Web of Science and Cochrane Library. Observational studies regarding the association between breast feeding and CRF in children and adolescents written in English or Spanish will be included. A Critical Appraisal Checklist for Analytical Cross Sectional Studies and The Newcastle-Ottawa Quality Assessment Scale for longitudinal studies will be used for quality assessment of included studies. Standardised mean differences of CRF by exclusive breastfeeding categories will be calculated as the primary outcome. Subgroup analyses and meta-regression will be performed based on the sources of heterogeneity.

ETHICS AND DISSEMINATION

This evidence-based systematic review will summarise the relevant information on the association of exclusive breast feeding and CRF in children and adolescents. The results will be disseminated by publication in a peer-reviewed journal. Given that the data used for this systematic review will be exclusively extracted from published studies, ethical approval will not be required.

PROSPERO REGISTRATION NUMBER

CRD42018082642.

Relationship between aerobic capacity with Birth Weight and breastfeeding patterns in children: A cross-sectional study

ABSTRACT Objective To analyze if aerobic capacity is related to Birth Weight and breastfeeding patterns in boys and girls, products of a term pregnancy and normal weight. Methods A representative sample of 230 Brazilian children (6-10 years old), born at term (after 37-weeks’ gestation) with normal weight (between 2.5 and 4.0kg). These children performed a Yo-Yo Test to estimate their aerobic capacity and mothers reported their children’s Birth Weight and breastfeeding patterns. The Pearson correlation coefficient was used to measure the association between aerobic capacity with Birth Weight and breastfeeding patterns. Results We did not observe any significant associations between aerobic capacity with Birth Weight and breastfeeding time in either sexes (p>0.05). Conclusion These results indicate that aerobic capacity is not related with Birth Weight or breastfeeding time in children born with normal weight and gestational age, suggesting that this complex physiological parameter does not appear to be determined by intrauterine factors that dictate the Birth Weight and breastfeeding patterns in the beginning of life.

Effect of Breastfeeding in Early Life on Cardiorespiratory and Physical Fitness: A Systematic Review and Meta-Analysis

BACKGROUND

Numerous studies have reported the associations between the type of feeding during infancy and subsequent chronic diseases.

OBJECTIVE

The objective of this systematic review is to synthesize the available literature concerning the effect of breastfeeding in infancy on physical and cardiorespiratory fitness in children and adolescents.

MATERIALS AND METHODS

We performed a comprehensive search of medical bibliographic databases to identify observational studies reporting the association between breastfeeding and cardiorespiratory or physical fitness. Random effects model was used for calculating the pooled estimates.

RESULTS

Three studies with 2,792 children were included in the meta-analysis. The mean value of VO₂max was similar between formula-fed and 1-3 months breastfed participants (standardized mean difference [SMD]: 0.1, 95% confidence intervals [CI]: -0.09 to 0.29, p = 0.31). There was no difference between 3 and 6 months breastfed (SMD: 0.17, 95% CI: -0.01 to 0.35, p = 0.06), >6 months breastfed (SMD: 0.37, 95% CI: -0.03 to 0.78, p = 0.07), and formula-fed children. The pooled SMD in handgrip strength was 0.09 (95% CI: -0.04 to 0.23; p = 0.17) between 1 and 3 months breastfed and formula-fed children .Nevertheless, 3-6 months (SMD: 0.13; 95% CI: 0.03-0.24) and >6 months (SMD: 0.19; 95% CI: 0.01-0.37) breastfeeding was associated with higher handgrip strength compared with formula-fed children. Breastfeeding for 1-3 (SMD: 0.20; 95% CI: 0.12-0.28), 3-6 (SMD: 0.27; 95% CI: 0.18-0.37), and >6 months (SMD: 0.34; 95% CI: 0.11-0.58) led to a significantly higher standing long-jump performance compared with formula feeding.

CONCLUSIONS

Breastfeeding shows beneficial effects on physical fitness, but further well-designed studies need to clarify effects of breastfeeding on cardiorespiratory fitness.

Associations between exclusive breastfeeding and physical fitness during childhood

PURPOSE

Exposure to breastfeeding improves the survival, health, and development of children; therefore, breast milk is recommended as the exclusive nutrient source for feeding term infants during the first 6 months. This cross-sectional study aimed to determine the possible association between exposure to exclusive breastfeeding and physical fitness performance in children and, if so, whether this association is influenced by the breastfeeding duration.

METHODS

A total of 2853 (52.3 % girls) European children from the IDEFICS study aged 6-11 years with complete data on physical fitness (cardiorespiratory fitness, muscular strength, flexibility, balance, speed) and exclusive breastfeeding duration (never, 1-3, 4-6, 7-12 months) were included in the present study. Multivariate and mixed linear regression models were estimated and adjusted for sex, age, birth weight, diet, physical activity, body mass index, and parental factors (age, body mass index, educational attainment).

RESULTS

We found a positive association between exclusive breastfeeding and lower-body explosive strength (β = 0.034) as well as flexibility (β = 0.028). We also found a positive association between breastfeeding and balance in boys (β = 0.039), while this association was negative in girls (β = -0.029). To improve lower-body explosive strength, 1-3 months of exclusive breastfeeding were enough; a longer duration did not lead to increasing benefit. In contrast, 4-6 months of breastfeeding were necessary to have any benefit on flexibility or balance, although this became nonsignificant after adjustment for body mass index and physical activity.

CONCLUSIONS

Exclusive breastfeeding seems a natural way of slightly improving some physical fitness components (mainly lower-body muscle strength) and thus future health.

Methods of milk expression for lactating women

BACKGROUND

Breastfeeding is important, however not all infants can feed at the breast and methods of expressing milk need evaluation.

OBJECTIVES

To assess acceptability, effectiveness, safety, effect on milk composition, contamination and costs of methods of milk expression.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (21 March 2016), handsearched relevant journals and conference proceedings, and contacted experts in the field to seek additional published or unpublished studies. We also examined reference lists of all relevant retrieved papers.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing methods at any time after birth.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.

MAIN RESULTS

This updated review includes 41 trials involving 2293 participants, with 22 trials involving 1339 participants contributing data for analysis. Twenty-six of the trials referred to mothers of infants in neonatal units (n = 1547) and 14 to mothers of healthy infants at home (n = 730), with one trial containing mothers of both neonatal and healthy older infants (n = 16). Eleven trials compared one or more types of pump versus hand expression and 14 studies compared one type of pump versus another type of pump, with three of these studies comparing both hand expression and pump types. Twenty studies compared a specific protocol or adjunct behaviour including sequential versus simultaneous pumping protocols, pumping frequency, provision of an education and support intervention, relaxation, breast massage, combining hand expression with pumping and a breast cleansing protocol.Due to heterogeneity in participants, interventions, and outcomes measured or reported, we were unable to pool findings for most of the specified outcomes. It was not possible therefore to produce a 'Summary of findings' table in this update. Most of the included results were derived from single studies. Trials took place in 14 countries under a variety of circumstances and were published from 1982 to 2015. Sixteen of the 30 trials that evaluated pumps or products had support from the manufacturers. The risk of bias of the included studies was variable. Primary outcomesOnly one of the 17 studies examining maternal satisfaction/acceptability with the method or adjunct behaviour provided data suitable for analysis. In this study, self-efficacy was assessed by asking mothers if they agreed or disagreed with the following statement: 'I don't want anyone to see me (hand expressing/pumping)'. The study found that mothers who were using the electric pump were more likely to agree with the statement compared to mothers hand expressing, (mean difference (MD) 0.70, 95% confidence interval (CI) 0.15 to 1.25; P = 0.01, participants = 68). Mothers who were hand expressing reported that the instructions for expression were clearer compared to the electric pump, (MD -0.40, 95% CI -0.75 to -0.05; P = 0.02, participants = 68). Descriptive reporting of satisfaction in the other studies varied in the measures used, did not indicate a clear preference for one pump type, although there was satisfaction with some relaxation and support interventions.We found no clinically significant differences between methods related to contamination of the milk that compared any type of pump to hand expression (risk ratio (RR) 1.13, 95% CI 0.79 to 1.61; P = 0.51, participants = 28), manual pump compared to hand expression, (MD 0.20, 95% CI -0.18 to 0.58; P = 0.30, participants = 142) a large electric pump compared to hand expression (MD 0.10, 95% CI -0.29 to 0.49; P = 0.61, participants = 123), or a large electric pump compared to a manual pump (MD -0.10, 95% CI -0.46 to 0.26; P = 0.59, participants = 141).The level of maternal breast or nipple pain or damage was similar in comparisons of a large electric pump to hand expression (MD 0.02, 95% CI -0.67 to 0.71; P = 0.96, participants = 68). A study comparing a manual and large electric pump, reported sore nipples in 7% for both groups and engorgement in 4% using a manual pump versus 6% using an electric pump; and in one study no nipple damage was reported in the hand-expression group, and one case of nipple damage in each of the manual pump and the large electric pump groups.One study examined adverse effects on infants, however as the infants did not all receive their mothers' expressed milk, we have not included the results. Secondary outcomesThe quantity of expressed milk obtained was increased, in some studies by a clinically significant amount, in interventions involving relaxation, music, warmth, massage, initiation of pumping, increased frequency of pumping and suitable breast shield size. Support programmes and simultaneous compared to sequential pumping did not show a difference in milk obtained. No pump consistently increased the milk volume obtained significantly.In relation to nutrient quality, hand expression or a large electric pump were found to provide higher protein than a manual pump, and hand expression provided higher sodium and lower potassium compared to a large electric pump or a manual pump. Fat content was higher with breast massage when pumping; no evidence of difference was found for energy content between methods.No consistent effect was found related to prolactin change or effect on oxytocin release with pump type or method. Economic aspects were not reported.

AUTHORS' CONCLUSIONS

The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low-cost interventions including initiation of milk expression sooner after birth when not feeding at the breast, relaxation, massage, warming the breasts, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Variation in nutrient content across methods may be relevant to some infants. Small sample sizes, large standard deviations, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings. Independently funded research is needed for more trials on hand expression, relaxation and other techniques that do not have a commercial potential.

Homage to the ‘H’ in developmental origins of health and disease

Abundant evidence exists linking maternal and paternal environments from pericopconception through the postnatal period to later risk to offspring diseases. This concept was first articulated by the late Sir David Barker and as such coined the Barker Hypothesis. The term was then mutated to Fetal Origins of Adult Disease and finally broadened to developmental origins of adult health and disease (DOHaD) in recognition that the perinatal environment can shape both health and disease in resulting offspring. Developmental exposure to various factors, including stress, obesity, caloric-rich diets and environmental chemicals can lead to detrimental offspring health outcomes. However, less attention has been paid to date on measures that parents can take to promote the long-term health of their offspring. In essence, have we neglected to consider the ‘H’ in DOHaD? It is the ‘H’ component that should be of primary concern to expecting mothers and fathers and those seeking to have children. While it may not be possible to eliminate exposure to all pernicious factors, prevention/remediation strategies may tip the scale to health rather than disease. By understanding disruptive DOHaD mechanisms, it may also illuminate behavioral modifications that parents can adapt before fertilization and throughout the neonatal period to promote the lifelong health of their male and female offspring. Three possibilities will be explored in the current review: parental exercise, probiotic supplementation and breastfeeding in the case of mothers. The ‘H’ paradigm should be the focus going forward as a healthy start can indeed last a lifetime.

Methods of milk expression for lactating women

BACKGROUND

This is an update of a 2008 Cochrane review. Breastfeeding is important. However, not all infants can feed at the breast and methods of expressing milk need evaluation.

OBJECTIVES

To assess acceptability, effectiveness, safety, effect on milk composition, contamination and cost implications of methods of milk expression.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2014), CINAHL (1982 to March 2014), conference proceedings, secondary references and contacted researchers.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing methods at any time after birth.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed trials, extracted data and assessed risk of bias.

MAIN RESULTS

This updated review includes 34 studies involving 1998 participants, with 17 trials involving 961 participants providing data for analysis. Eight studies compared one or more types of pump versus hand expression and 14 studies compared one type of pump versus another type of pump, with three of these studies comparing both hand expression and multiple pump types. Fifteen studies compared a specific protocol or adjunct behaviour including sequential versus simultaneous pumping protocols (five studies), pumping > 4 times per day versus < 3 times per day (one study), provision of a milk expression education and support intervention to mothers of preterm infants versus no provision (one study), provision of audio/visual relaxation to mothers of preterm infants versus no specific relaxation (two studies), commencing pumping within one hour of delivery versus between one to six hours (one study), breast massage before or during pumping versus no massage (two studies, of which one also tested a second behaviour), therapeutic touch versus none (one study), warming breasts before pumping versus not warming breasts (one study), combining hand expression with pumping versus pumping alone (one study) and a breast cleansing protocol versus no protocol (one study).There were insufficient comparable data on outcomes to undertake meta-analysis and data reported relates to evidence from single studies.Only one of the 17 studies examining maternal satisfaction/acceptability provided data in a way that could be analysed, reporting that mothers assigned to the pumping group had more agreement with the statement 'I don't want anyone to see me pumping' than mothers in the hand expression group and the statement 'I don't want anyone to see me hand expressing' (n = 68, mean difference (MD) -0.70, 95% confidence interval (CI) -1.25 to -0.15, P = 0.01), and that mothers found instructions for hand expression were clearer than for pumping (n = 68, MD 0.40, 95% CI 0.05 to 0.75, P = 0.02). No evidence of a difference was found between methods related to adverse effects of milk contamination (one study, n = 28, risk ratio (RR) 0.89, 95% CI 0.62 to 1.27, P = 0.51), (one study, n = 142 milk samples, MD 0.20, 95% CI -0.18 to 0.58, P = 0.30), (one study, n = 123 milk samples, MD 0.10, 95% CI -0.29 to 0.49, P = 0.61), (one study, n = 141 milk samples, MD -0.10, 95% CI -0.46 to 0.26, P = 0.59 ); or level of maternal breast or nipple pain or damage (one study, n = 68, MD 0.02, 95% CI -0.67 to 0.71, P = 0.96).For the secondary outcomes, greater volume was obtained when mothers with infants in a neonatal unit were provided with a relaxation tape or music-listening interventions to use while pumping, when the breasts was warmed before pumping or massaged while pumping.Initiation of milk pumping within 60 minutes of birth of a very low birthweight infant obtained higher mean milk quantity in the first week than the group who initiated pumping later. No evidence of difference in volume was found with simultaneous or sequential pumping or between pumps studied. Differences between methods was found for sodium, potassium, protein and fat constituents; no evidence of difference was found for energy content.No consistent effect was found related to prolactin change or effect on oxytocin release with pump type or method. Economic aspects were not reported.Most studies were classified as unclear or low risk of bias. Most studies did not provide any information regarding blinding of outcome assessment. Fifteen of the 25 studies that evaluated pumps or products had support from the manufacturers.

AUTHORS' CONCLUSIONS

The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low-cost interventions including early initiation when not feeding at the breast, listening to relaxation music, massage and warming of the breasts, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Small sample sizes, large standard deviations, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings.

The association between breastfeeding and childhood obesity: a meta-analysis

Background

The increase in childhood obesity is a serious public health concern. Several studies have indicated that breastfed children have a lower risk of childhood obesity than those who were not breastfed, while other studies have provided conflicting evidence. The objective of this meta-analysis was to investigate the association between breastfeeding and the risk of childhood obesity.

Methods

The PubMed, EMBASE and CINAHL Plus with Full Text databases were systematically searched from start date to 1^st August 2014. Based on the meta-analysis, pooled adjusted odds ratio (AOR) and 95% confidence interval (CI) were calculated. I² statistic was used to evaluate the between-study heterogeneity. Funnel plots and Fail-safe N were used to assess publication bias and reliability of results, and results from both Egger test and Begg test were reported.

Results

Twenty-five studies with a total of 226,508 participants were included in this meta-analysis. The studies’ publication dates ranged from 1997 to 2014, and they examined the population of 12 countries. Results showed that breastfeeding was associated with a significantly reduced risk of obesity in children (AOR = 0.78; 95% CI: 0.74, 0.81). Categorical analysis of 17 studies revealed a dose-response effect between breastfeeding duration and reduced risk of childhood obesity.

Conclusion

Results of our meta-analysis suggest that breastfeeding is a significant protective factor against obesity in children.

Breastfeeding up to two years of age or beyond and its influence on child growth and development: a systematic review

A systematic review was undertaken to identify studies describing the global prevalence of breastfeeding up to two years of age or beyond and its effects on child growth and development. The MEDLINE and LILACS databases were searched without any language or date restrictions, retrieving 3,561 titles. All retrieved titles, 453 abstracts and 49 full-text articles were read. Articles with maximum breastfeeding duration of over two years were included. An analysis was carried out of 19 articles that met the inclusion criteria resulting in a combined prevalence of breastfeeding at two years of age of 33 % (95%CI: 0.23; 0.42). Increasing trends towards breastfeeding up to two years of age or beyond were observed in the past decades in South Asia. The six studies analyzing the effects of breastfeeding up to two years of age or beyond on child growth showed contradictory results. No association was found with child development. It is concluded that evidence on the medium-term effects of breastfeeding up to two years of age or beyond is scarce and contradictory. Hence, further research is needed regarding this practice.

Bicycling to school is associated with improvements in physical fitness over a 6-year follow-up period in Swedish children

OBJECTIVE

To examine whether modes of commuting to school at baseline and changes in commuting were related to 6-year changes in cardiorespiratory fitness in youth.

METHODS

A total of 262 (142 girls) Swedish children (9 years at entry) were measured at baseline (1998/9) and follow-up (2004/5). Mode of commuting to school was assessed by questionnaire and fitness by a maximal bicycle test.

RESULTS

At baseline, 34% of children used passive modes of commuting (e.g., car, motorcycle, bus, train), 54% walked, and 12% bicycled to school. Six years later the percentage of bicyclists increased 19% and the percentage of walkers decreased 19%. On average, children who bicycled to school increased their fitness 13% (p=0.03) more than those who used passive modes and 20% (p=0.002) more than those who walked. Children who used passive modes or walked at baseline and bicycled to school at 6 years later increased their fitness 14% (p=0.001) more than those who remained using passive modes or walking at follow-up.

CONCLUSIONS

Implementing initiatives that encourage bicycling to school may be a useful strategy to increase cardiorespiratory fitness of children.