Breastfeeding can offer significant nutritional and non-nutritional benefits to both infant and mother. The World Health Organisation (WHO) recommends that, whenever possible, infants should be fed exclusively on breast milk until six months of age and that breast milk should continue as part of the diet for at least two years. 

During the initial phases of human development nutrition has the potential to positively or negatively affect organ function, and thereby predispose individuals to a later onset of optimal health or disease. The short and long-term breastfeeding supports the optimal development of the immune system, motor control and cognitive ability. 

The initial months after birth may also serve as a critical window for the development of obesity, a condition which is of significant concern to public health in Ireland at present. Parental feeding practices during infancy, such as the timing of solid food introduction, may be a key modifiable determinant of childhood obesity. 

The promotion of breastfeeding among mothers in Ireland has been a key government health policy since the mid-1990s. However, the prevalence of breastfeeding is still relatively low. Findings from the 2011 Growing Up in Ireland study revealed that just under 50% of babies were being breastfed when they left hospital and 57% had ever received breast milk. Among those who had never breastfed the most frequent reason for not doing so was ‘formula feeding preferable’ (48%); the next most frequent reason was ‘inconvenience/ fatigue (17%). Every effort should be made to ensure mothers are offered support and encouragement to initiate and maintain breastfeeding.

Introduction

Breastfeeding is a complex and exceptionally adaptive function. It is an intricate process of interaction between mother and child that is more than simply a means of nutrition [1]. While infants will make daily leaps in neurocognitive, motor and social development, they are completely dependent on parents and guardians to feed and nurture them [2]. Thus, it should be no surprise that what occurs in the first months of life may be essential to lifelong nutritional status [1][3]. 

The World Health Organisation (WHO) recommends that, whenever possible, infants should be fed exclusively on breast milk until 6 months of age and that breast milk should continue as part of the diet for at least 2 years [4], yet globally only 38% of infants are breastfed [5]. The concept that nutrition during the initial phases of human development has the potential to alter organ function, and ultimately predispose individuals to a later onset of disease, is an area of great interest within medical science and of significant concern to public health [6].

The Benefits of Breastfeeding to the Infant

Breastfeeding offers numerous short and long term benefits for infant health. It may protect against morbidity and mortality from infectious diseases [6]. Systematic reviews on the long term effects of breastfeeding have found that participants who were breastfed experienced lower mean blood pressure and total cholesterol. Evidence also suggests that breastfeeding is associated with increased cognitive development in childhood [7]. Furthermore, the evidence suggests that breastfeeding may have a small protective long term effect on the prevalence of obesity [7].  Breastfeeding also correlates with a reduction in a range of infectious and non-infectious illnesses including diarrhoea, respiratory illness, ear infection, type 1 diabetes mellitus, coeliac disease, inflammatory bowel disease, childhood cancer, allergies and asthma [7].
 
Breastfeeding also has many positive benefits beyond nutritional status. Colostrum, produced in the first days of breastfeeding, contains over 90 known components, including vitamins, minerals, amino acids and immune and growth factors. In addition, its mild laxative effect encourages the passing of the infants first stool, the meconium [8]. Furthermore, the neonatal period is particularly critical as the newborn is immediately exposed to a large number of microorganisms and foreign proteins, and breastfeeding is important for the provision of immune-modulating factors which may exert a decisive impact on the breastfed baby’s developing defence [9]. Human milk is quantitatively different than either soy or bovine formula. Numerous bioactive factors are exclusive to human milk including specific human growth hormones and growth factors. For instance, breast milk reinforces mucosal defences by providing secretory IgA (SIgA) and IgM (SIgM) antibodies, and delivering immune cells, cytokines and high concentrations of oligosaccharides [8].

The Benefits of Breastfeeding in Maternal Health

Maternal health must also be considered in relation to breastfeeding.  A study by Schwarz et al. [10]  which examined the data of 139,681 postmenopausal women, found that those who breastfed their children were less likely to have developed hypertension, diabetes, hyperlipidaemia and cardiovascular disease when postmenopausal [10]. Women who had a cumulative lifetime duration of lactation greater than 12 months were approximately 10% less likely to have developed cardiovascular disease than parous women who had never breast-fed at 7.9 years, the median duration of follow-up [10].  Thus, the authors concluded that lactation may play a significant role in reducing risk of cardiovascular disease [10]. Lactation increases a mother’s metabolic expenditure by an estimated 480 kcal/day. Lactating mothers lose more weight in the postpartum period than mothers who do not breastfeed [10][11].  

Breastfeeding has been proposed to be associated with postpartum depression. However this link has been underexplored in the literature [1][12][13]. A proposed mechanism is that lactation is associated with an attenuated stress response, involving cortisol and the lactogenic hormones oxytocin and prolactin, which appear to have both antidepressant and anxiolytic effects [12]. A bidirectional relationship has been identified between breastfeeding and depression, with prenatal depressive symptomatology predicting less breastfeeding postpartum and early breastfeeding predicting less depressive symptomatology later in the postpartum [13].    

                                             
Breastfeeding and Obesity

The prevalence of obesity is a topical issue in Ireland at present, and indeed a major public health crisis around the world [14]. The initial months after birth may serve as a critical window for the development of obesity [14][15]. Parental feeding practices during infancy, such as the timing of solid food introduction, may be a key modifiable determinant of childhood obesity [15]. 

A prospective pre-birth cohort study of 847 children from Project Viva, a longitudinal pre-birth cohort of mother–offspring pairs in Boston, Massachusetts, revealed that the introduction of solids before the age of 4 months was associated with a six-fold increase in the risk of obesity at age 3 years among infants who were never breastfed or who stopped breastfeeding before the age of 4 months [15] The authors stated that the association was not explained by rapid early growth [15]. One possible explanation for the benefit of breastfeeding might be that breastfed children learn appetite control and that this control remains after the introduction of solid food. This lack of appetite control may lead to overfeeding in bottle-fed infants due to lack of parental responsiveness to infant satiety cues [2][16].

Breastfeeding in Ireland

The promotion of breastfeeding among mothers in Ireland has been a key government health policy since the mid-1990s. However, the prevalence of breastfeeding is still relatively low [17] In 2008 the Health Service Executive (HSE) commissioned a national study to determine the rate and duration of breastfeeding in Ireland. This national study, the first since 1986, measured breastfeeding rates following discharge from hospital. It aimed to assess the rate of exclusive and partial breastfeeding at three critical periods: from birth to 48 hours, at 3 to 4 months, and at 6 to 7 months [18].
 
The authors found that 56% of mothers who responded to phase 2 of the survey (3 to 4 months post-natal) had initiated breastfeeding at birth. Amongst mothers who initiated breastfeeding, those who were aged 40 to 44 were the most likely to be exclusively breastfeeding at 3 to 4 months (48%). The length of hospital stay was not found to be a significant factor on rates of breastfeeding. At 6 to 7 months, 18% of the 461 mothers who were breastfeeding at 3 to 4 months remained exclusively breastfeeding. This was just 6% of the 1002 mothers who had breastfed their infants at birth, and only 2.4% of the 2527 mothers who joined the study.

Fundamentally, the study revealed relevant and potentially modifiable factors associated with breastfeeding initiation in Ireland. Peers were found to be influential in a mother’s choice of infant feeding method. Professional, managerial and technical workers were more likely to initiate breastfeeding than those in non-manual, semi-skilled, skilled or manual employment. The younger the mother when she gave birth, the less likely she was to initiate breastfeeding [18].

A WHO Ireland country profile, completed in 2013, examined nationally representative data from 2008 and revealed that the prevalence of exclusive breastfeeding at 6 months of age was 2.5% in Ireland [19]. Taking these findings into consideration, it appears that there is a need for a comprehensive, national system of monitoring breastfeeding rates at predetermined intervals [16][18]. More recently, findings from the 2011 Growing Up in Ireland study revealed that just under 50% of babies were being breastfed when they left hospital and 57% in total had ever received breast milk [17]. Furthermore, infants whose mothers were born outside Ireland were much more likely to be breastfed that infants whose mothers were born in Ireland (83% compared to 48%). Mothers who breastfed typically stopped when the infant was three months old. The most frequent reason for discontinuing breastfeeding among those who had previously breastfed was ‘not enough milk/hungry baby’ (37%). Among those who had never breastfed, the most frequent reason for not doing so was ‘formula feeding preferable’ (48%) or ‘inconvenience/fatigue’ (17%) [17]. 

Factors Affecting Breastfeeding Initiation

The decision about feeding is often made by the last trimester of pregnancy. Information given during prenatal care is extremely influential and it is apparent that both advertising and healthcare providers influence a women’s choice [20]. A study revealed that the leading reasons for discontinuation of breastfeeding included: concerns of insufficient milk production (45%); infants dissatisfaction with breast milk (42%); difficulty nursing (24%); sore, cracked or bleeding nipples (17%); and return to work/school (16%) [20].
 
For many first time mothers the prospect of breast feeding may be daunting. A 2012 Cochrane review of 52 studies from 21 countries concluded that all women should be offered support to breastfeed their babies to increase the duration and exclusivity of breastfeeding [21].  This support may be offered either by professional or lay and peer supporters, or a combination of both. Strategies that rely mainly on face-to face support are more likely to succeed. Importantly, support for which women are expected to initiate first contact, or reactive support, is unlikely to be effective. Women should be offered scheduled visits on an on-going basis so they can predict that support will be available [21]. It also imperative that women are educated regarding the option to continue to try to breastfeed, even weeks into formula feeding. It must also be acknowledged that for some mothers breastfeeding is not possible. This may be frustrating and distressing for the mothers, and they must also receive adequate support.
From a financial aspect, breastfeeding offers considerable savings compared to formula feeding [20]. Still, the formula industry has reversed feeding trends from primarily breastfeeding to primarily formula feeding through pervasive marketing strategies targeting hospitals, health providers, and the general public [20]. The impact of the infant formula industry and advertising of infant formula on breastfeeding practices is largely unknown and almost certainly complex. It is of note that Ireland produces some 15% of the world’s infant formula [22] so it follows that the influence of the industry in Ireland is not likely to be negligible.

Conclusions

The decision to breastfeed is deeply personal and individual. Breastfeeding can offer significant nutritional and non-nutritional benefits to the infant and the mother, throughout their lives. Therefore, the support and education around breastfeeding should be viewed as a major public health issue. Efforts to promote breastfeeding can succeed, but they must become a public health priority. The contribution of breastfeeding to public health should be considered and every effort should be made to ensure mothers are offered support and encouragement to initiate and maintain this invaluable, natural interaction.

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