Breast-feeding and child health in the United States

Human Milk Cells Contain Numerous miRNAs that May Change with Milk Removal and Regulate Multiple Physiological Processes

Human milk (HM) is a complex biofluid conferring nutritional, protective and developmental components for optimal infant growth. Amongst these are maternal cells, which change in response to feeding and were recently shown to be a rich source of miRNAs. We used next generation sequencing to characterize the cellular miRNA profile of HM collected before and after feeding. HM cells conserved higher miRNA content than the lipid and skim HM fractions or other body fluids, in accordance with previous studies. In total, 1467 known mature and 1996 novel miRNAs were identified, with 89 high-confidence novel miRNAs. HM cell content was higher post-feeding (p < 0.05), and was positively associated with total miRNA content (p = 0.014) and species number (p < 0.001). This coincided with upregulation of 29 known and 2 novel miRNAs, and downregulation of 4 known and 1 novel miRNAs post-feeding, but no statistically significant change in expression was found for the remaining miRNAs. These findings suggest that feeding may influence the miRNA content of HM cells. The most highly and differentially expressed miRNAs were key regulators of milk components, with potential diagnostic value in lactation performance. They are also involved in the control of body fluid balance, thirst, appetite, immune response, and development, implicating their functional significance for the infant.

INTERGENERATIONAL EDUCATIONAL ATTAINMENT, FAMILY CHARACTERISTICS AND CHILD OBESITY

This study used US National Longitudinal Study of Youth data to explore how exposure to different socioeconomic conditions (proxied by maternal education) before birth can shape child weight. Using endogenous selection regression models, the findings suggest that educational selectivity affects weight gain. Mothers whose mothers graduated from high school were more likely to complete high school, and mothers reared in an intact family had higher levels of education. However, mothers who had given birth as a teenager had the same educational outcomes as mothers who gave birth in their post-teenage years. Based on this intergenerational educational selectivity, caretaking (e.g. breast-feeding) was found to be associated with a lower child body mass index (BMI), while negative maternal characteristics (e.g. mothers with high BMIs) were associated with higher child BMIs. Thus, educational selectivity influences child health through values passed on to the child and the lifestyle in which the child is reared. Maternal education may be tied to parenting, which relates to child obesity risk.

Breast-feeding and childhood hospitalizations for infections

BACKGROUND

Infectious disease is a leading cause of morbidity and hospitalization for infants and children. During infancy, breast-feeding protects against infectious diseases, particularly respiratory infections, gastrointestinal infections, and otitis media. Little is known about the longer-term impact of breast-feeding on infectious disease in children.

METHODS

We investigated the relationship between infant feeding and childhood hospitalizations from respiratory and gastrointestinal infections in a population-based birth cohort of 8327 children born in 1997 and followed for 8 years. The main outcomes were public hospital admissions for respiratory infections, gastrointestinal infections, and all infectious diseases. Cox regression was used to assess time to first hospitalization.

RESULTS

Breast-feeding only (no formula-feeding) for 3 or more months was associated with a lower risk of hospital admission in the first 6 months of life for respiratory infections (hazard ratio = 0.64 [95% confidence interval = 0.42-0.97]), gastrointestinal infections (0.51 [0.25-1.05]), and any infection (0.61 [0.44-0.85]), adjusted for sex, type of hospital at birth, and household income. Partial breast-feeding (both breast-feeding and formula-feeding) in the first 3 months also reduced hospitalizations from infections but with smaller effect sizes. Beyond 6 months of age, there was no association between breast-feeding status at 3 months and hospitalization for infectious disease.

CONCLUSIONS

Giving breast milk and no formula for at least 3 months substantially reduced hospital admissions for many infectious diseases in the first 6 months of life, when children are most vulnerable.

Analysis of advertisements of infant food commercialized in the city of Natal, Rio Grande do Norte, Brazil

The advertising about maternal milk substitutes has been pointed as one of the factors responsible for the breastfeeding low rates. In this way, legal support was created to assure that the use of such products would not interfere on the healthy breastfeeding habit of the population. This study, developed between June 2006 and May 2008 in the city of Natal, state of Rio Grande do Norte, analyzed the food advertisements divulged under the validity of Law # 11.265/2006, which controls in Brazil the food commercialization and the publicity addressed to parents or keepers of nursling and children in the first childhood. 220 advertisements, being 141 of technical-scientific nature, and 79 for strictly commercial promotion, were collected and evaluated according to legal requirements. The results from this analysis showed that 100% of the advertisements of technical-scientific nature overstepped the clause V; 18.4% the clause IV and 14.2% the clauses I, II and III of article 19th of Law # 11265/2006. In 42% of the advertisements strictly for commercial promotion, the mandatory information mentioned at clauses I and II of the article 5th were not shown. In 8.7% of the advertisements containing such information, it was placed in an area that embarrassed its identification and reading, due to used fonts size and/or color; similarly as occurred with the information required by article 19th, in the advertisements of technical-scientific nature.

Session 1: Feeding and infant development breast-feeding and immune function

The newborn receives, via the placenta, maternal IgG antibodies against the microbes present in its surroundings, but such antibodies have a pro-inflammatory action, initiating the complement system and phagocytes. Although the host defence mechanisms of the neonate that involve inflammatory reactivity are somewhat inefficient, this defence system can still have catabolic effects. Breast-feeding compensates for this relative inefficiency of host defence in the neonate by providing considerable amounts of secretory IgA antibodies directed particularly against the microbial flora of the mother and her environment. These antibodies bind the microbes that are appearing on the infant's mucosal membranes, preventing activation of the pro-inflammatory defence. The major milk protein lactoferrin can destroy microbes and reduce inflammatory responses. The non-absorbed milk oligosaccharides block attachment of microbes to the infant's mucosae, preventing infections. The milk may contain anti-secretory factor, which is anti-inflammatory, preventing mastitis in mothers and diarrhoea in infants. Numerous additional factors in the milk are of unknown function, although IL-7 is linked to the larger size of the thymus and the enhanced development of intestinal Tgammadelta lymphocytes in breast-fed compared with non-breast-fed infants. Several additional components in the milk may help to explain why breast-feeding can reduce infant mortality, protecting against neonatal septicaemia and meningitis. It is therefore important to start breast-feeding immediately. Protection is also apparent against diarrhoea, respiratory infections and otitis media. There may be protection against urinary tract infections and necrotizing enterocolitis, and possibly also against allergy and certain other immunological diseases, and tumours. In conclusion, breast-feeding provides a very broad multifactorial anti-inflammatory defence for the infant.

Recall of age of weaning and other breastfeeding variables

BACKGROUND

Many studies of the impact of breastfeeding on child or maternal health have relied on data reported retrospectively. The goal of this study was to assess recall accuracy among breastfeeding mothers of retrospectively collected data on age of weaning, reasons for cessation, breast pain, lactation mastitis, and pumping.

METHODS

Women in Michigan and Nebraska, U.S.A. were interviewed by telephone every 3 weeks during the first 3 months after the birth of their child, and mailed a questionnaire at 6 months. A subset was interviewed again by telephone approximately 1-3.5 years after the birth. The results for the three recall periods, collected 1994-1998, were compared using correlation, linear and Cox regression analysis, and sensitivity and specificity estimates.

RESULTS

The 184 participants were aged 18-42, mostly white (95%) and 63% had an older child. The age of weaning tended to be overestimated in interviews 1-3.5 years after birth compared to those within 3 weeks of the event, by approximately one month for 1-3.5 year recall and two weeks for 6-month recall (p < 0.001 in both cases). Recall accuracy of reasons for weaning varied greatly by reason, with mastitis and return to work having the most recall validity. The sensitivity of 1-3.5 year recall of mastitis was 80%, but was only 54% for nipple cracks or sores.

CONCLUSION

Breastfeeding duration among short-term breastfeeders tended to be somewhat overestimated when measured at 1-3.5 years post-partum. Reporting of other breastfeeding characteristics had variable reliability. Studies employing retrospective breastfeeding data should consider the possibility of such errors.

The baby-friendly hospital initiative increases breastfeeding rates in a US neonatal intensive care unit

This study evaluated the impact of a Baby-Friendly designation on breastfeeding rates in a US neonatal intensive care unit (NICU). The medical records of all surviving infants directly admitted to the Boston Medical Center's level III, 15-bed NICU in 1995 (before Baby-Friendly policies were implemented) and 1999 (when Baby-Friendly status was granted) were reviewed. Infants receiving any breast milk by any means during the first week of enteral feeds were considered to have initiated breastfeeding. Maternal and infant demographics for 1995 and 1999 were comparable. The NICU breastfeeding initiation rate increased from 34.6% (1995) to 74.4% (1999) (P < .001). Among 2-week-old infants, the proportion receiving any breast milk rose from 27.9% (1995) to 65.9% (1999) (P < .001), and the proportion receiving breast milk exclusively rose from 9.3% (1995) to 39% (1999) (P = .002). The implementation of Baby-Friendly policies leading to a Baby-Friendly designation was associated with increased breastfeeding initiation and duration rates.

[Assessment of the promotion of breastfeeding in public and private maternities of São Paulo city, Brazil]

OBJECTIVE

The World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) carried out a study to compare and evaluate the practices of protecting, promoting and supporting breastfeeding in public and private hospitals using the "ten steps" of the Hospital Initiative (BFHI) as a reference parameter.

METHODS

Forty-five hospitals of the municipality of São Paulo participated in the study. Data on the practices of infant feeding were collected by interviewing nurseries' supervisors of all public hospitals (26), and from a random sample of private hospitals (19), corresponding to a third of the total, during the years 1996-1997.

RESULTS

More than a quarter of the public hospitals and more than one third of the private hospitals did not comply with any of the BFHI steps. Seven of the "ten steps" were observed in only two public hospitals. In general, practices of protection, promotion, and support of breastfeeding were seen at a higher frequency in public hospitals.

CONCLUSIONS

The present study shows that practices considered detrimental to the onset and progressing of breastfeeding - unnecessary separation of the mother and her newborn, restrictions regarding the length of time and frequency of breastfeeding, use of pre-lacteal foods and supplements - are still quite frequently observed in public and private hospitals within the city of São Paulo. Given the benefits of breastfeeding for both the mother's and their children's health, and the important role maternities play for an early and successful onset of breastfeeding, it is paramount that the BFHI patterns be adopted by hospitals within the municipality of São Paulo.

Use of an intensity ratio to describe breastfeeding exclusivity in a national sample

Breastfeeding behavior in a sample of 1863 mother-infant pairs was examined using data from the 1988 National Maternal-Infant Health Survey. Breastfeeding behavior was operationalized as an intensity ratio, calculated as the number of breast milk feeds (on average in 24 hours) divided by the total number of all liquid feeds (on average in 24 hours), with a range from 0 to 1.0. During the first month postpartum, 61% of the sample reported exclusive breastfeeding, declining to 31% during months 2-3 postpartum and to 13% during months 4-6 postpartum. This decline was consistent with the linear decline in the mean intensity ratio, .82, .55, and .31, respectively, during the same three time periods. A higher breastfeeding intensity ratio was significantly associated with longer duration of breastfeeding, up to 1 year of life. Intensity ratio, as a measure of exclusivity, is a useful outcome measure for monitoring breastfeeding behavior.

Host defense benefits of breastfeeding for the infant. Effect of breastfeeding duration and exclusivity

Breastfeeding confers lifesaving protection against infectious illness among disadvantaged populations. As a result, breastfeeding promotion has an important part in child health programs throughout the world. In this article, the evidence regarding the host defense benefits of breastfeeding for term infants of normal birth weight is reviewed, with an emphasis on recent information from industrialized countries regarding how the degree and duration of breastfeeding affect infant health.

Anticonvulsant use during lactation

The issue of prescribing anticonvulsant drugs during lactation is clinically important, but also complex. Data for some drugs are completely lacking and for other drugs information is only available from single dose or short term studies or case reports. Moreover, limited knowledge exists about the practical impact of the drug concentrations found in breast milk and there are great methodological problems in the assessment of possible adverse drug reactions in infants. Nevertheless, based on current knowledge, some recommendations can be suggested. Treatment with carbamazepine, valproic acid (sodium valproate) and phenytoin is considered compatible with breastfeeding. Treatment with ethosuximide or phenobarbital (phenobarbitone)/primidone should most probably be regarded as potentially unsafe and close clinical monitoring of the infant is recommended if it is decided to continue breastfeeding. Occasional or short term treatment with benzodiazepines could be considered as compatible with breastfeeding, although maternal diazepam treatment has caused sedation in suckling infants after short term use. During long term use of benzodiazepines, infants should be observed for signs of sedation and poor suckling. Only very limited clinical data are available for the new generation anticonvulsant drugs and no clearcut recommendations can be made until further data are present. If it is decided to continue breast feeding during treatment with these drugs, the infant should be monitored for possible adverse effects. In general, the drug should be given in the lowest effective dose, guided by maternal serum or plasma drug concentration monitoring. If breast feeding is avoided at times of peak drug levels in milk, the exposure of the infant can be reduced to some extent. As breast milk has considerable advantages over formula milk, the benefits of continuing breast feeding should always be taken into consideration in the risk-benefit analysis.

Analgesics and breast-feeding: safety considerations

The issue of prescription of analgesics during lactation is clinically important but also complex. Most of the information available is based on single dose or short term studies, and for many drugs only a single or a few case reports have been published. As great methodological problems exist in the assessment of possible adverse drug reactions in neonates and infants, there is limited knowledge about the practical impact of the, often very low, concentrations found. Nevertheless, some recommendations can be made. Breast-feeding during maternal treatment with paracetamol (acetaminophen) should be regarded as being safe. Short term use of nonsteroidal anti-inflammatory drugs seems to be compatible with breast-feeding. For long term treatment, short-acting agents without active metabolites, such as ibuprofen, should possibly be preferred. The use of aspirin (acetylsalicylic acid) in single doses should not pose any significant risks to the suckling infant. Use of codeine is probably compatible with breast-feeding, although the effects of long term exposure have not been fully elucidated. For propoxyphene, it seems unlikely that the suckling infant will ingest amounts that will cause any detrimental effects during short term treatment. However, it cannot be excluded that significant amounts of the metabolite norpropoxyphene may arise in the suckling infant during long term exposure. Treatment of the mother with single doses of morphine or pethidine (meperidine) is not expected to cause any risk for the suckling infant. Repeated administration of pethidine, in contrast to morphine, affects the suckling infant negatively. Thus, morphine should be preferred in lactating mothers. However, during long term treatment with morphine, the importance of uninterrupted breast-feeding should be assessed on an individual basis against the potential risk of adverse drug effects in the infant. If it is decided to continue breast-feeding the infant should be observed for possible adverse effects. In general, if treatment of a lactating mother with an analgesic drug is considered necessary, the lowest effective maternal dose should be given. Moreover, infant exposure can be further reduced if breast-feeding is avoided at times of peak drug concentration in milk. As breast milk has considerable nutritional, immunological and other advantages over formula milk, the possible risks to the infant should always, and on an individual basis, be carefully weighed against the benefits of continuing breast-feeding.

Accumulation of factors influencing children's middle ear disease: risk factor modelling on a large population cohort

STUDY OBJECTIVES

Data were analysed from a large national birth cohort to examine cumulative and interactive prediction from various risk factors for childhood middle ear disease, and to resolve conflicting evidence arising from small and incompletely controlled studies. The large sample size permitted appropriate covariate adjustment to give generality, and permit demographic breakdown of the risk factors.

SETTING

A large multi-purpose longitudinal birth cohort study of all births in the UK in one week in 1970, with multiple questionnaire sweeps.

PARTICIPANTS

Over 13,000 children were entered into the original cohort. Data on over 12,000 children were available at the five year follow up.

MAIN OUTCOME MEASURES

For children at 5 years, parent reported data were available on health and social factors including data on two markers for middle ear disease: the occurrence of purulent (nonwax) ear discharge and suspected or confirmed hearing difficulty.

MAIN RESULTS

In those children who had ever had reported hearing difficulty (suspected or confirmed), after control for socioeconomic status, three of the classic factors (male sex, mother's smoking habits since birth, and attending day care) were significantly more frequent. In those who had ever had ear discharge reported, only mother's smoking habit since birth was significantly more frequent. However, it showed an orderly dose response relation. In addition, a derived general child health score was found to be significantly associated with both the middle ear disease markers. Control for this variable in the analysis of those having reported hearing difficulty reduced the effect size of mother's smoking habit, but it remained statistically significant. For reported ear discharge, even after control for the general health score and social index, mother's smoking habits and day care attendance were both significant predictors. Mother's (but not father's) smoking habits and day care attendance were found to be significant risk factors for middle ear disease. Breast feeding effects were weak and did not generally survive statistical control.

CONCLUSIONS

A child having all three risk factors (attends day care, a mother who smokes, and male sex) is 3.4 times more likely to have problems with hearing than a child who has none, based on cumulative risk. Further studies should focus on preventative risk modification and well specified intervention.

Breast feeding on campus: personal experiences, beliefs, and attitudes of the university community

Breast feeding a new baby is a special challenge for college students and university employees. Although success is usually associated with availability of support from the community, little is known about the social context for breast feeding on campus. Personal breast feeding experiences, beliefs about outcomes of breast-feeding and bottle feeding, attitudes toward breast feeding and bottle feeding, and regard for appropriateness of various settings for breast feeding in the campus community were investigated. One hundred seven students, faculty, staff, and administrators at a North Central state university participated in the study. Almost all reported at least one personal breast-feeding experience. Benefits of breast feeding over bottle feeding were acknowledged; however, the university community regarded both feeding methods favorably and saw practical advantages to bottle feeding. Personal spaces, such as infant home or family car, were regarded as more appropriate for breast feeding than public settings. Implications for promotion, support, and protection of breast feeding on campus are discussed.

A tendência da prática da amamentação no Brasil nas décadas de 70 e 80

A prática da amamentação sofreu um declínio em todo o mundo, levando a conseqüências desastrosas para a saúde das crianças e suas mães. A partir da década de 70 iniciou-se um verdadeiro movimento mundial para o retorno à amamentação, sendo que no Brasil, estudos realizados em algumas cidades indicam o possível sucesso deste movimento no País. Este estudo teve por objetivo descrever a trajetória recente do aleitamento materno no Brasil, em diferentes estratos populacionais, compa-rando duas pesquisas nacionais (ENDEF/75 e PNSN/89). Empregou-se a análise de probitos, que permite estimar freqüências da amamentação a partir de regressões lineares ponderadas, utilizando o teste de aderência de Kolmogorov-Smirnov para verificar a adequação dos modelos obtidos. Verificou-se uma expansão considerável da prática da amamentação no País. Esta tedência ocorreu em todos os estratos da população, porém o aumento da prática da amamentação foi mais acentuado na área urbana, na região Centro-Sul do país, entre as mulheres de maior poder aquisitivo e de maior escolaridade.

Breast-feeding education of obstetrics-gynecology residents and practitioners

OBJECTIVE

Our purpose was to assess breast-feeding education, knowledge, attitudes, and practices among resident and practicing obstetrician-gynecologists.

STUDY DESIGN

A mailed survey was administered to a national sample of resident and practicing obstetrician-gynecologists.

RESULTS

Response rates were 64% for residents and 69% for practitioners. Residency training included limited opportunity for direct patient interaction regarding breast-feeding; 60% of practitioners recommended that training devote more time to breast-feeding counseling skills. Only 38% of residents reported that obstetric faculty presented breast-feeding topics; more common sources were nursing staff and other residents. Practitioners rated themselves as more effective in meeting the needs of breast-feeding patients than were residents; prior personal breast-feeding experience was a significant influence on perceived effectiveness. Almost all respondents agreed that obstretician-gynecologists have a role in breast-feeding promotion, but significant deficits in knowledge of breast-feeding benefits and clinical management were found.

CONCLUSION

Residency training and continuing education programs should create opportunities to practice breast-feeding promotion skills and emphasize management of common lactation problems.