Infant feeding patterns on Mauritius Island, 1991

The 1991 Mauritius Contraceptive Prevalence Survey (CPS) included a special module on infant feeding patterns in Mauritius. Since 1985, when a similar CPS was conducted, the incidence of breast-feeding has fallen from 86% to 72%. The duration of any breast-feeding among those breast-fed remained constant at 13.6 months. The module allowed for an assessment of the World Health Organization (WHO) breast-feeding indicators on exclusive breast-feeding, timely complementary feeding and continued breast-feeding. Only 16% of infants 0–3 months old are exclusively breast-fed; only 29% of infants 6–9 months old receive breast milk and complementary foods and only 27% of children 12–15 months are still breast-fed. These patterns of limited breast-feeding and early supplementation may signal future declines in breast-feeding for other African and Asian countries. Published by Elsevier Science Ltd     

Infant feeding in the 20th century: formula and beikost

The early years of the 20th century were notable for improvements in general sanitation, dairying practices and milk handling. Most infants were breast-fed, often with some formula feeding as well. Availability of the home icebox permitted safe storage of milk and infant formula, and by the 1920s, feeding of orange juice and cod liver oil greatly decreased the incidence of scurvy and rickets. Use of evaporated milk for formula preparation decreased bacterial contamination and curd tension of infant formulas. From 1930 through the 1960s, breast-feeding declined and cow's milk and beikost were introduced into the diet at earlier and earlier ages. Although commercially prepared formulas, including iron-fortified formulas replaced home-prepared formulas, few infants were breast-fed or formula fed after 4-6 mo of age. Iron deficiency was prevalent. From 1970 through 1999, a resurgence of breast-feeding was associated with a prolongation of formula feeding and an increase in usage of iron-fortified formulas. By the end of the century, formula feeding of older infants had largely replaced feeding of fresh cow's milk and the prevalence of iron deficiency had greatly decreased.     

An overlap of breastfeeding during late pregnancy is associated with subsequent changes in colostrum composition and morbidity rates among Peruvian infants and their mothers

An overlap of breast-feeding and late pregnancy is associated with decreased intake of human milk and reduced infant growth. We evaluated the association of an overlap with macronutrient and immunological components of milk, infant urinary IgA, and infant and maternal morbidity. On d 2 and 1 mo postpartum, staff measured 24-h intake of breast milk and collected samples from 133 Peruvian women; 68 had breast-fed during the last trimester of pregnancy (BFP) and 65 had not breast-fed during pregnancy (NBFP). Data on maternal and infant anthropometry and health were collected for 1 mo. On d 2, lactose and lysozyme concentrations were higher, total lysozyme intake was higher and concentration and total intake of lactoferrin were lower in the BFP than the NBFP group (P < 0.05). The total 1-mo IgA intake was lower among BFP than NBFP infants (P = 0.01). Urinary IgA concentration was correlated with breast milk IgA concentration (r = 0.29; P = 0.01) but not with breast-feeding during pregnancy. An overlap was not associated with diarrhea but BFP infants were 5 times as likely to have a cough for at least 7 d than NBFP infants (P < 0.05). Reported mastitis was rare and occurred only in the NBFP group (P = 0.05). An overlap of breast-feeding and late pregnancy was associated with changes in milk composition, an increased frequency in symptoms of infant respiratory illness but decreased reported mastitis. Further in-depth studies are warranted to determine the cumulative effects associated with a breast-feeding/pregnancy overlap on infant and maternal outcomes.     

Nutrition survey in Tabasco, Mexico: patterns of infant feeding

Information on infant feeding was collected from 149 mothers of 744 children born over a period of 25 yr in an area of Tabasco, Mexico which has experienced rapid economic development. From 1953 to 1978, there was an increase in bottle-feeding, primarily as a supplement to breast-feeding, while the proportion of infants exclusively breast-fed declined from 69 to 48%. This trend was accompanied by a decrease in the average duration of lactation: the percentage of infants breast-fed 12 months or more declined from 73 to 45%. Mothers living within the area of an agricultural development project completed in 1973 were more likely to bottle-feed than mothers outside the project. The consequences of supplemental bottle-feeding for continued lactation, infant health, and child spacing require further investigation.     

Preliminary data from demographic and health surveys on infant feeding in 20 developing countries

This study describes infant feeding practices in developing countries, specifically complementary liquids and foods in the first year of life. Data were compiled from Demographic and Health Surveys conducted from 1999 to 2003. We analyzed data from those countries with available data, including results for child-level 24-h and 7-d food and fluid intakes. We used datasets from 20 countries with information on >35,000 infants categorized by age: 0-6 and 6-12 mo. For analysis, we grouped data for fluids other than breast milk as water, other milk (e.g., tinned, powdered, animal), infant formula, and other liquids (e.g., fruit juice, herbal tea, sugar water). All specific solid foods were grouped as any solid foods. We present data on breast-feeding and maternal-reported fluid and solid intake by infants in a 24-h period, for individual countries, and in a pooled analysis. Pooled data show that 96.6% of 0- to 6- and 87.9% of 6- to 12-mo-old infants were currently breast-fed. Reported feeding of other fluids was lower among 0- to 6-mo-olds than 6- to 12-mo-olds: water (45.9 vs. 87.4%), other milk products (11.9 vs. 29.6%), infant formula (9.0 vs. 15.1%), and other liquids (15.1 vs. 41.0%). Pooled analysis showed that 21.9% of mothers reported feeding 0- to 6-mo-old infants some type of solid food, and 80.1% of mothers reported feeding solids to 6- to 12-mo-olds. These survey data show that other milks, other liquids, and solid foods are each much more commonly fed throughout infancy than commercial infant formulas in the countries studied.     

Breast-feeding among the urban poor in southern Brazil: reasons for termination in the first 6 months of life

A study of breast-feeding practices over the first 6 months of life among a cohort of urban poor infants in southern Brazil indicated that the median duration of breast-feeding was 18 weeks, and at 6 months 41% of the infants were still being breast-fed. The duration of breast-feeding was significantly associated with the following: the infant's sex, mother's colour, type of first feed, timing of the first breast-feed, breast-feeding regimen and frequency of breast-feeding at 1 month, and the use of hormonal contraceptives by the mother. The following were significant risk factors for early termination of breast-feeding: the infant's sex, type of first feed, use of supplementary feeds, frequency of breast-feeding, feeding regimen, weight-for-age, and weight-for-age after controlling for birth weight. Dissatisfaction with their infant's growth rate was the most frequent reason given by mothers for supplementing the diets of infants who were exclusively breast-fed in the first 3 months of life. Also, the mothers' perception that their milk output was inadequate was the most frequent reason expressed for stopping breast-feeding in the first 4 months. The roles of health services and family support in providing favourable conditions for increasing the duration of breast-feeding in the study population are discussed, as well as the possibility of bias being introduced into studies of the relationship between infant feeding and growth by the effect of the infant's rate of growth on the mother's decision to continue breast-feeding.     

The reasons for early weaning among mothers in Teheran.

In order to identify the reasons for early weaning in Teheran, we interviewed 900 mothers using a systematic randomized sampling method. A total of 15% of the mothers were illiterate, 93% were housewives, and 97% had given birth in hospitals. Only 3% of the newborns benefited from rooming-in facilities in hospital, and 68% were bottle-fed while still in hospital. In 3.1% of cases the mother had not breast-fed her newborn at all. Of those who had breast-fed their infant, 38% used only their own milk, whereas 62% used a combination of breast milk and infant formula. The median duration of breast-feeding was 16 months (mean, 14 months). A total of 74% of mothers who used supplementary formula and 39% of those who had completely stopped breast-feeding blamed milk insufficiency, although 67% of these mothers had reached this conclusion only because their infants cried or were irritable. The following factors had a negative influence on the duration of breast-feeding: use of supplementary formula and of estrogen-containing oral contraceptives; fathers with high incomes; and mothers with a high educational level. In contrast, the mother''s religious motive to breast-feed and her insistence on breast-feeding had a positive impact. Unfortunately, 21% of the mothers started using supplementary formula during the first month postpartum, and two-thirds before the end of the fourth month. Every month that bottle-feeding was started prematurely shortened the duration of breast-feeding by 20 days.(ABSTRACT TRUNCATED AT 250 WORDS)     

The duration of breast-feeding. A longitudinal prospective study in Denmark.

A longitudinal prospective study was performed to investigate the total duration of breast-feeding. Three hundred and sixty-six mothers were followed-up until 3 years after delivery. At 1 month 93% were breast-feeding, at 3 months 73%, at 6 months 52%, at 1 year 20% and 1% breast-fed more than 3 years. Correlations were found between duration of breast-feeding and maternal age, education and social class. Mothers who had breast-fed an older child usually breast-fed the next child for a period of similar length. Solid food was most frequently introduced when the infants were 4 months old. At 6 months 4% were still exclusively breast-fed. Breast-feeding has become popular: only 1% did not want to breast-feed at all and 89% of mothers intended to breast-feed their children for 6 months or more. Even though the mothers now breast-feed longer than earlier, only 39% succeeded in breast-feeding for as long as or longer than they had intended.     

Stereoacuity at age 3.5 y in children born full-term is associated with prenatal and postnatal dietary factors: a report from a population-based cohort study

BACKGROUND: Observational studies suggested that breast-feeding benefits the visual development of preterm children, which has been attributed to the presence of docosahexaenoic acid (DHA) in breast milk but not most formula milks. Randomized studies showed that preterm children require a dietary supply of DHA in the first few weeks of life for optimal visual development, but it is unclear whether full-term children experience similar benefits from breast milk or DHA supplements. OBJECTIVE: The objective of this study was to compare stereoacuity at age 3.5 y in healthy, full-term children who were breast-fed and in similar children who had not been breast-fed after adjustment for socioeconomic status and maternal diet. DESIGN: Prospectively collected data on maternal diet during pregnancy (including intake of oily fish), the child's diet, and the socioeconomic status of the family were examined. Stereoacuity at age 3.5 y was assessed. RESULTS: Children who had been breast-fed for 4 mo were more likely to achieve high-grade stereopsis, or stereoscopic vision, than were children who had not been breast-fed (adjusted odds ratio: 2.77; 95% CI: 1.54, 4.97). The mother's antenatal blood DHA content was associated with her intake of oily fish (P < 0.0001). Children whose mothers ate oily fish during pregnancy were also more likely to achieve high-grade stereopsis than were children whose mothers did not eat oily fish (adjusted odds ratio: 1.57; 95% CI: 1.00, 2.45). CONCLUSIONS: The results of this study suggest that for full-term infants, breast-feeding is associated with enhanced stereopsis at age 3.5 y, as is a maternal DHA-rich antenatal diet, irrespective of later infant feeding practice.     

Infant feeding and HIV

Mother-to-child HIV transmission is the main cause of HIV infection in children. About two thirds of children infected vertically are infected during pregnancy and around the time of delivery, while the remainder are infected during breast-feeding. Although breast-feeding tends to be the best way to feed infants, substituting breast-feeding can reduce the risk of mother-to-child HIV transmission when mothers are HIV-seropositive. However, when breast milk substitutes are used, infants are 5 times more likely to have bacterial infections than are breast-fed infants, even in the context of good hygiene. Where hygiene is poor, artificially fed infants may be 20 times more likely to die from diarrhea than are breast-fed infants. HIV-positive women need information on the risks and benefits of breast-feeding and of the various alternatives, and support in deciding which method is best. Infant feeding options are discussed.     

Transmission of HIV-1 in the Breast-Feeding Process

Current laboratory techniques cannot distinguish the mode of vertical transmission (intrauterine, intrapartum, or postnatal) of human immunodeficiency virus type 1 (HIV-1) from mother to infant. The ability to transmit HIV-1 via breastfeeding has been established in 24 case reports, primarily involving mothers who seroconvert after delivery. Whether breast-feeding adds a notable additional risk of HIV-1 infection to the risk from pregnancy is controversial. The importance of the duration and intensity of breast-feeding in modulating the outcome of HIV transmission via breast milk also remains unclear. Factors in breast milk may play important roles in an infant's susceptibility to infection with HIV and in the expression of the virus. Pasteurization and storage enhance the intrinsic, antiviral properties of human milk. Banked human milk is pasteurized to destroy the HIV-1 virus but retains properties that may be helpful to infants of HIV-1-positive mothers in developed countries where breastfeeding is not recommended. For infants in populations where the infant mortality rate is high, the risk of death associated with HIV infection acquired via breast milk is lower than the risk associated with not being breast-fed. J Am Diet Assoc. 1996; 96:267-274.     

Infant exposure to dioxin-like compounds in breast milk

We used a one-compartment, first-order pharmacokinetic model to predict the infant body burden of dioxin-like compounds that results from breast-feeding. Validation testing of the model showed a good match between predictions and measurements of dioxin toxic equivalents (TEQs) in breast-fed infants, and the exercise highlighted the importance of the assumption of the rate of dissipation of TEQs in the infant. We evaluated five nursing scenarios: no nursing (i.e., formula only), and nursing for 6 weeks, 6 months, 1 year, and 2 years. We assumed that an infant weighs 3.3 kg at birth and is exposed to a total of 800 pg TEQ/day by consumption of breast milk, leading to an estimated body weight-based dose of 242 pg TEQ/kg-day, which drops to 18 pg TEQ/kg-day after 1 year. This decline is due to declines in dioxin concentration in mother's milk and infant body weight increases. This range is significantly higher, on a body-weight basis, than adult TEQ exposure, which has been estimated to average about 1 pg TEQ/kg-day. For the nursing scenarios of >or= 6 months, we predict that body burdens (expressed as a body lipid concentration) peak at around 9 weeks at 44 ppt TEQ lipid. We predict that the body burden of the formula-fed infants will remain below 10 ppt TEQ lipid during the first year. These results compare to the current adult average body burden of 25 ppt TEQ lipid. We also found that an infant who had been breast-fed for 1 year had an accumulated dose 6 times higher than a 1-year-old infant who had not been breast-fed. For a 70-year lifetime, individuals who had been breast-fed had an accumulated dose 3-18% higher than individuals who had not been breast-fed.     

Incidence and duration of breast-feeding in Mexican-American infants, 1970-1982

The Mexican-American component of the Hispanic Health and Nutrition Examination Survey (HHANES-MA) was used to examine the breast-feeding behavior of 2402 infants born between 1970 and 1982. The proportion of infants ever breast-fed increased substantially in recent years. Weighted proportions were 30.7% for 1970-1974, 38.1% for 1975-1978, and 47.6% for 1979-1982. By use of logistic regression models, children born into households with a college-educated head were shown to be more likely to be breast-fed than were other children; breast-feeding was also positively associated with birth weight. Infants in households for which the preferred interview language was Spanish were more likely to be breast-fed than were infants living in households for which the interview was conducted in English. Analysis of the factors influencing the distribution of weaning times among infants was less definitive because reported weaning times are heaped on multiples of 3 mo. The gathering of current-status, or status quo, information on infant feeding is urged for data collection in future studies.     

Breast-feeding is associated with improved growth in length, but not weight, in rural Senegalese toddlers

BACKGROUND: Prolonged breast-feeding is frequently associated with malnutrition in less-developed countries, even after adjustment for socioeconomic confounders. However, in rural Senegal, breast-feeding is prolonged when the child is stunted. OBJECTIVE: We aimed to test whether the lower height-for-age of children weaned late is explained by their height before weaning or whether prolonged breast-feeding is associated with impaired growth. DESIGN: A cohort of 443 Senegalese children recruited from dispensaries at 2 mo of age were visited in their homes at 6-mo intervals when they were approximately 1.5 to 3 y of age. Weight, length, arm circumference, and triceps skinfold thickness were measured. Six-month increments were analyzed in relation to breast-feeding (breast-fed compared with weaned children or breast-feeding duration), season, and maternal housing with use of multiple linear regression. RESULTS: The mean duration of breast-feeding was 24.1 mo (quartiles 1 and 3: 21.9 and 26.4). Height-for-age at the age of 3 y was negatively associated with age at weaning (P < 0.01), but this association disappeared after adjustment for height-for-age in infancy. Length increments were significantly greater in both the second and third years of life in children breast-fed for longer durations (P < 0.05) and tended to be greater in breast-fed than in weaned children in the second year of life (P = 0.05). In the third year of life, breast-fed children had greater length increments than did weaned children in the subgroup with poor housing (P for interaction < 0.05). Growth in weight did not differ significantly according to breast-feeding. CONCLUSION: Prolonged breast-feeding improved linear growth, and the negative relation between height-for-age and duration of breast-feeding was due to reverse causality.     

Evolution of infant nutrition

Homo sapiens has developed during the course of over two million years. The social and physical conditions of life, the availability of milk and infant foods as well as the presence of diseases have all undergone radical transformations from the Stone Age, at first without and then with fire, to the hunter-gatherer, farmer-herder, agricultural and, now, developed societies. These changes in the human environment may have induced modifications in the length of pregnancy, the development of the neonate at birth, the duration of lactation, the composition of breast milk and use of weaning foods and milk substitutes. Darwinian selection for the nutrient, anti-infective and other components of breast milk may have been determined by the effects of nutrition, through genetic variations in milk composition, on the survival of infants and perhaps also on fecundity and disease resistance in later adult life. Today Darwinian selection may no longer be effective in maintaining or modifying human mammary function, because modern hygienic environments, together with the availability of nutritionally adequate breast-milk substitutes, permit infant survival even under conditions of total lactational failure. National and international promulgations strictly control the composition of infant formulas offered as breast-milk substitutes or as weaning foods. These recommendations are modified as beliefs suggest, and research indicates, the effects of nutrients and other factors on the health and well-being of the child. Preliminary observations on child health have often proved valuable in furthering research. Unquestioning acceptance of apparently desirable, but untested, epidemiological associations have led to unexpected but dangerous iatrogenic problems. Recommendations for change cannot safely be made without proper comparisons with present products and procedures under practical conditions. Such tests are time consuming and require protocols of appropriate statistical design and power while still meeting the required sociological and ethical constraints, but are essential to identify possible harmful effects of any proposed change. It is suggested that no novel ingredients should be added, or major changes permitted in any component, until appropriate trials have established the value and safety of the proposed modifications. Breast-feeding is vital to maximize infant survival in developing countries. There are major difficulties in assessing any differences in morbidity and mortality of breast-fed v. artificially reared infants in the developed world. Carefully controlled studies with comparisons of health and well-being, not only in infancy but throughout life, are desirable if the effects of infant nutrition on adult well-being, suggested by epidemiological studies, are to be validated and ultimately applied. There are considerable variations in the composition of breast milk. This variance suggests that it may ultimately be possible to design formulas better able to meet the needs of individual infants than the milk available from the mother's breast.     

Infant exposure to chemicals in breast milk in the United States: what we need to learn from a breast milk monitoring program

The presence of environmental chemicals in breast milk has gained increased attention from regulatory agencies and groups advocating women's and children's health. As the published literature on chemicals in breast milk has grown, there remains a paucity of data on parameters related to infant exposure via breast-feeding, particularly those with a time-dependent nature. This information is necessary for performing exposure assessments without heavy reliance on default assumptions. Although most experts agree that, except in unusual situations, breast-feeding is the preferred nutrition, a better understanding of an infant's level of exposure to environmental chemicals is essential, particularly in the United States where information is sparse. In this paper, we review extant data on two parameters needed to conduct realistic exposure assessments for breast-fed infants: a) levels of chemicals in human milk in the United States (and trends for dioxins/furans); and b) elimination kinetics (depuration) of chemicals from the mother during breast-feeding. The limitations of the existing data restrict our ability to predict infant body burdens of these chemicals from breast-feeding. Although the data indicate a decrease in breast milk dioxin toxic equivalents over time for several countries, the results for the United States are ambiguous. Whereas available information supports the inclusion of depuration when estimating exposures from breast-feeding, the data do not support selection of a specific rate of depuration. A program of breast milk monitoring would serve to provide the information needed to assess infant exposures during breast-feeding and develop scientifically sound information on benefits and risks of breast-feeding in the United States.     

Advances in our understanding of the biology of human milk and its effects on the offspring

There is an intense interest in the effects of breast-feeding on the offspring and in understanding the mechanisms behind these effects. More than 50 papers are published monthly on topics such as the influence of breast-feeding on aspects of growth, immune-related effects, mental development, and noncommunicable diseases. Most breast-feeding data are observational; confounding can be difficult to rule out because some maternal factors are associated with both breast-feeding and infant outcomes (e.g., obesity and mental development). The most important short-term immunological benefit of breast-feeding is the protection against infectious diseases. There is also some evidence of lower prevalence of inflammatory bowel diseases, childhood cancers, and type I diabetes in breast-fed infants, suggesting that breast-feeding influences the development of the infant's own immune system. One of the most consistent findings of breast-feeding is a positive effect on later intelligence tests with a few test points advantage for breast-fed infants. In the last few years, several systematic reviews and meta-analyses have examined the effect of breast-feeding on noncommunicable diseases. There seems to be a small protective effect against later overweight and obesity. Blood pressure and blood cholesterol seem to be slightly lower in breast-fed infants; however, the few studies examining breast-feeding and the risk of coronary heart disease in later life did not find an association. Recent data have suggested that breast-feeding can program the insulin-like growth factor-I axis, as 3 studies found that breast-fed infants are taller as adults.     

Nutritional aspects of human lactation

This paper reviews the literature on the incidence and duration of breast-feeding in various countries, the volume and composition of breast milk, the health and nutrition of breast-fed babies as judged by growth and morbidity, maternal nutritional requirements during lactation, and the effect of prolonged lactation on maternal health. It appears that lactation can be as well sustained by impoverished as by affluent mothers, and that even in communities where malnutrition is common the average growth of infants is satisfactory up to the age of about 3 months on a diet of breast milk alone. Breast milk appears to have specific anti-infective properties, but prolonged breast-feeding will not prevent infections among older infants reared in a poor environment. The authors believe that breast-feeding is the best form of nutrition for the young infant and deplore its decline in modern industrial societies. The recommendations of various FAO/WHO Expert Groups on nutritional intakes during lactation are summarized. The need for an increased daily energy intake of 4.2 MJ (1 000 kcal) is questioned, and an increase of 2.5 MJ (600 kcal) is suggested. Data on the effect of prolonged lactation on the health of the mother are scanty; body weight appears to be maintained even among poorly nourished mothers. The authors stress the need for well-planned and technically adequate studies of the material and psychological factors involved in breast feeding.     

母乳喂养流行病学调查随访研究:Ⅲ.影响母乳量因素的逐步回归分析

本文用流行病学调查随访研究方法观察了461例乳母分娩后6个月内的母乳喂养情况,并用逐步回归分析方法筛选影响母乳量的因素。经逐步回归分析,最后共筛选出10个因素。其中产后一个月后每天喂奶次数。产后一个月内每天喂奶次数、规律喂奶、月经恢复时间四个因素与母乳量呈正相关(即能增加母乳量);母亲食欲差、家族缺奶史、婴儿发育差、母亲孕乳期患病、药物避孕、乳头内陷六个因素与母乳量呈负相关(即减少母乳量)。影响母乳量的因素是多方面的,用逐步回归分析方法进行分析,比较接近实际情况,也是把多因素分析方法应用于妇幼卫生保健领域中的一种尝试。