Breast feeding is a natural contraceptive and prevents disease and death in infants, linking infant mortality and birth rates

Breastfeeding and Mortality Under 2 Years of Age in Sub-Saharan Africa

BACKGROUND

Several studies have investigated the association of breastfeeding status with offspring mortality in Africa, but most studies were from one center only or had limited statistical power to draw robust conclusions.

METHODS

Data came from 75 nationally representative cross-sectional Demographic and Health Surveys in 35 countries in sub-Saharan Africa conducted between 2000 and 2016. Our study relied on 217 112 individuals aged 4 days to 23 months for breastfeeding pattern analysis, 161 322 individuals aged 6 to 23 months for breastfeeding history analysis, and 104 427 individuals aged 12 to 23 months for breastfeeding duration analysis.

RESULTS

Compared with children aged 4 days to 23 months exclusively breastfed in the first 3 days of life, those not breastfed had a high risk of mortality at <2 years of age (odds ratio [OR] = 13.45; 95% confidence interval [CI] = 11.43-15.83). Young children who were predominantly breastfed or partially breastfed had moderately increased risk of mortality at <2 years of age (OR = 1.11, 95% CI = 1.03-1.21 for predominant pattern; OR = 1.12, 95% CI = 0.99-1.27 for partial pattern). Compared with children aged 6 to 23 months who were breastfed within the first 6 months of life, those not breastfed had a high risk of mortality (OR = 5.65; 95% CI = 4.27-7.47). Compared with children aged 12 to 23 months who were breastfed for ≥6 months, those who were breastfed for shorter periods had a higher risk of mortality (OR = 2.78, 95% CI = 1.45-5.32 for duration of <3 months; OR = 5.28, 95% CI = 3.24-8.61 for those who were not breastfed).

CONCLUSIONS

Our findings support exclusive breastfeeding during the first 6 months of life and continued breastfeeding up to 2 years of age recommended by the World Health Organization for reducing mortality of children <2 years old in sub-Saharan Africa.

Optimal breastfeeding practices and infant and child mortality: a systematic review and meta-analysis

AIM

To synthesise the evidence for effects of optimal breastfeeding on all-cause and infection-related mortality in infants and children aged 0-23 months.

METHODS

We conducted a systematic review to compare the effect of predominant, partial or nonbreastfeeding versus exclusive breastfeeding on mortality rates in the first six months of life and effect of no versus any breastfeeding on mortality rates between 6 and 23 months of age. A systematic literature search was conducted in PubMed, Cochrane CENTRAL and CABI.

RESULTS

The risk of all-cause mortality was higher in predominantly (RR 1.5), partially (RR 4.8) and nonbreastfed (RR14.4) infants compared to exclusively breastfed infants 0-5 months of age. Children 6-11 and 12-23 months of age who were not breastfed had 1.8- and 2.0-fold higher risk of mortality, respectively, when compared to those who were breastfed. Risk of infection-related mortality in 0-5 months was higher in predominantly (RR 1.7), partially (RR 4.56) and nonbreastfed (RR 8.66) infants compared to exclusive breastfed infants. The risk was twofold higher in nonbreastfed children when compared to breastfed children aged 6-23 months.

CONCLUSION

The findings underscore the importance of optimal breastfeeding practices during infancy and early childhood.

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.

Deaths and years of life lost due to suboptimal breast-feeding among children in the developing world: a global ecological risk assessment

OBJECTIVE

We estimate attributable fractions, deaths and years of life lost among infants and children < or = 2 years of age due to suboptimal breast-feeding in developing countries.

DESIGN

We compare actual practices to a minimum exposure pattern consisting of exclusive breast-feeding for infants < or = 6 months of age and continued breast-feeding for older infants and children < or = 2 years of age. For infants, we consider deaths due to diarrhoeal disease and lower respiratory tract infections, and deaths due to all causes are considered in the second year of life. Outcome measures are attributable fractions, deaths, years of life lost and offsetting deaths potentially caused by mother-to-child transmission of HIV through breast-feeding.

SETTING

Developing countries.

SUBJECTS

Infants and children < or = 2 years of age.

RESULTS

Attributable fractions for deaths due to diarrhoeal disease and lower respiratory tract infections are 55% and 53%, respectively, for the first six months of infancy, 20% and 18% for the second six months, and are 20% for all-cause deaths in the second year of life. Globally, as many as 1.45 million lives (117 million years of life) are lost due to suboptimal breast-feeding in developing countries. Offsetting deaths caused by mother-to-child transmission of HIV through breast-feeding could be as high as 242,000 (18.8 million years of life lost) if relevant World Health Organization recommendations are not followed.

CONCLUSIONS

The size of the gap between current practice and recommendations is striking when one considers breast-feeding involves no out-of-pocket costs, that there exists universal consensus on best practices, and that implementing current international recommendations could potentially save 1.45 million children's lives each year.

Patterns for the initiation of breastfeeding in humans

Establishment of lactation has important biological and emotional health consequences for the newborn. Even so, substantial variation within a culture and among different cultures is seen in the onset of breastfeeding. Parametric mixture models are used to explore this variation and to uncover general human patterns for the initiation of breastfeeding. The model components reflect two hypothesized patterns of behavior. The first component is a "natural" pattern of breastfeeding that reflects, to some extent, a general mammalian behavior. The second component arises through culturally mediated behaviors that affect the initiation of breastfeeding. The model was fit by maximum likelihood to interval- and right-censored observations on 26220 mother-infant pairs collected from 25 previously published studies of breastfeeding behavior. Both model components were clearly statistically identified. Effects of cultural and geographic covariates were found to have significant effects on all components of the model. Although there is clear evidence for two distinct patterns of behavior in the initiation of breastfeeding, the results suggest that learned behaviors play an important role in mediating even "natural" breastfeeding behavior.

Breast feeding and infant mortality

The evidence linking bottle feeding to infant and early childhood mortality has been reviewed. Ecological studies of national time trends in infant mortality do not parallel breast feeding trends in those countries, and indicate that falling death rates are more likely to be related to better health care facilities and social conditions. Direct studies of deaths provide some contradictory findings; meta-analyses are not informative because of the many differences in statistical and sample methodology. The methodology exhibited in most studies is more likely to have over- rather than under-estimated a relationship between bottle feeding and infant mortality. Retrospective analyses must take account of changes in feeding pattern due to early signs of illness. Prospective population studies able to account for large numbers of potential confounders provide the best estimates, especially if proportional hazards models are used. Two such studies have been carried out--both showed protective effects of breast feeding.