In order to be able to properly support families, it is important that professionals are knowledgeable about the benefits of breastfeeding. It is also imperative that professionals understand the physiology of breastfeeding and the problems that mothers and babies may face in establishing breastfeeding. Equally importantly, families need to have confidence that professionals can give them accurate and up to date advice if they cannot, or choose not to, breastfeed for any reason.

Physiology

Breastmilk is not made up of a single substance, nor is it always the same. It varies during the course of lactation, between individual feeds and between mothers.

The first milk produced by the breast after birth is colostrum. A thick, yellow milk, it is produced in relatively small volumes (approximately 100ml/day). Although not providing large amounts of nutrition, it is high in protein, mostly as immunoglobulins (antibodies) such as secretory IgA. It is also a rich source of minerals and vitamins A, D and B12.

The second stage of milk production is transitional milk. This commences between about days 3 – 7 and coincides with a marked increase in volume (also known as the milk ‘coming in’).

Mature milk is produced from about day 14 until the number of feeds per day decreases significantly. It contains secretory IgA with specificity to antigens, including potential pathogens, as well as lymphocytes, macrophages (which produce lactoferrin and lysozymes), cytokines and other substances, such as bifidus factor (which enhances the growth of lactobacillus bifidus), all of which help to protect the vulnerable newborn against infection. Milk production is infant led and is rarely limited by the mother’s capacity to synthesise milk; mothers can, for instance, produce enough milk for twins and in some cases triplets.

Milk composition varies during the course of a feed:

• Fore milk is at the beginning of a milk feed and is a watery liquid, almost blue in colour. It contains a high percentage of fluid, is richer in lactose and has a relatively low fat content. This is often referred to as the thirst quenching part of a feed.
• Hind milk is produced towards the end of a feed and is relatively high in fat and therefore energy dense and is whiter in colour than fore milk. This milk is thought to help signal to the infant that the feed is coming to an end. If babies do not receive this milk, they may receive insufficient energy and their growth may falter. It is therefore important that mothers are counselled to empty one breast before offering the other breast (if required) to her infant.

It takes 3 – 6 weeks for breastfeeding to become fully established and it is particularly important that babies are fed ‘on demand’ during this period so that milk production is appropriate for the baby’s requirements. The use of additional fluids, such as water and infant formula, during this period is not recommended, as it interferes with the establishment of breastfeeding. Some infants may be able to manage bottles as well as breast feeds after this time, but some quickly realise that bottle feeding is an easier way to get milk. Families need to be warned of this potential problem if they wish to give bottles as well as breastfeeding.

Benefits of breastfeeding to the infant

1. Contamination - breastmilk is always at the right temperature and the correct concentration and lowers or eliminates the risk of contamination by bacterial pathogens. Though not a real issue in the West, this is of particular importance in the developing world where access to clean water may be an issue.
2. Gastroenteritis – several studies have shown a reduction in risk of diarrhoeal disease in breastfed infants^1,2. This is thought to be due to factors in the milk such as secretory IgA, lactoferrin and other antibodies as previously described. Recent research has shown that nucleotides and prebiotics in breastmilk may also help to promote appropriate bacterial colonisation in the infant gut (see later in article).
3. Respiratory infection – rates of upper respiratory tract infection (URTI) are known to be lower in breastfed infants and this protection may be long-lasting; one study found a reduced risk respiratory infection in seven year olds who had been breastfed for at least 15 weeks as infants.
4. Necrotising enterocolitis (NEC) – this is a potentially fatal gastrointestinal condition, mostly found in preterm babies. Studies have shown a reduction in incidence in infants who are breastmilk fed^4,5.
5. Obesity – there is increasing evidence that breastfeeding helps to protect against obesity later in life^6,7,8. It is well recognised that breastfed infants gain weight more slowly than their formula fed contemporaries. It is increasingly believed that rapid weight gain at key points in infancy could be linked to adverse health outcomes – including obesity – in later life^8,9.*
6. Atopy – this remains somewhat controversial, but it is generally accepted that breastmilk at least partially protects against atopic conditions such as eczema and asthma, particularly in infants with a positive family history^3,10,11

Benefits currently undergoing research

1. Improved cognitive development – this effect was first noted in preterm infants¹², but has subsequently also been found in term infants¹³. Infants who have been breastmilk fed are known to have higher IQ levels; this has led to changes in infant formula composition (see later). However, a recent meta-analysis has cast doubt on whether these effects are due to breastmilk or other factors, including differences in socioeconomic profiles between mothers who breastfeed and those who formula feed¹⁴.
2. Insulin dependent diabetes – several studies have shown a reduction in the incidence of childhood insulin dependent diabetes in high risk families¹⁵. However, it is not clear whether this is a benefit of breastfeeding or a form of cows’ milk protein allergy.
3. Inflammatory bowel disease – it has been suggested that breastfeeding may be protective, but further research is needed¹⁶.

Possible Benefits for the Mother

1. Reduced risk of breast cancer - there is some evidence that breastfeeding may reduce the risk of breast cancer in pre-menopausal women. A recent meta-analysis found a decrease in risk of breast cancer of 4.3% for every 12 months of breastfeeding¹⁷
2. Reduced risk of ovarian cancer – there is less evidence for this, however there is general agreement that the risk may be reduced in women who breastfeed¹⁸
3. Possible reduced risk of osteoporosis – although this remains unclear and controversial
4. Post partum weight loss – this is frequently cited as a benefit of breastfeeding. However, evidence of any benefit has only been found with breastfeeding of greater than 6 months duration¹⁹
5. Emotional and psychological benefits of breastfeeding – this is a very controversial area, which has been poorly studied.

Possible Benefits for the Mother

1. Reduced risk of breast cancer - there is some evidence that breastfeeding may reduce the risk of breast cancer in pre-menopausal women. A recent meta-analysis found a decrease in risk of breast cancer of 4.3% for every 12 months of breastfeeding¹⁷
2. Reduced risk of ovarian cancer – there is less evidence for this, however there is general agreement that the risk may be reduced in women who breastfeed¹⁸
3. Possible reduced risk of osteoporosis – although this remains unclear and controversial
4. Post partum weight loss – this is frequently cited as a benefit of breastfeeding. However, evidence of any benefit has only been found with breastfeeding of greater than 6 months duration¹⁹
5. Emotional and psychological benefits of breastfeeding – this is a very controversial area, which has been poorly studied.

Contraindications to breastfeeding

1. HIV/AIDS – in the UK it is recommended that the benefits of breastfeeding are outweighed by the risk of transmission of HIV to the baby. This is not so in developing countries where poor availability of formula milks and clean water make breastfeeding the safer choice.
2. Breast surgery – some breast surgeries e.g. mastectomies, breast reduction, implants may make breastfeeding impossible. Women should seek further advice from their midwife and doctors.
3. Some drugs, e.g. some antidepressants and some seizure medication, may contraindicate breastfeeding. Again, women should ask their caregivers or pharmacists for further advice.

Reality of breastfeeding

Clearly there are demonstrable benefits to breastfeeding. However, information alone will never be sufficient to improve the initiation and duration of breastfeeding. Mothers need to be taught the practical skills and given all necessary support – particularly in the early days – if all (or at least most) women who wish to breastfeed are going to be successful. The 2005 Infant Feeding Survey²⁰ has recently been published and provides an insight into how infants are fed in the UK in the twenty first century and in particular the experience of breastfeeding mothers. The incidence of breastfeeding (that is the percentage of babies who have ever been put to the breast) in the UK has increased from 69% in 2000 to 76% in 2005; rates were highest in England (78%) and lowest in Northern Ireland (63%). Mothers in the survey are getting older and better educated – two factors which tend to lead to higher breastfeeding rates. However, for the first time in twenty years, when these factors are taken into account, breastfeeding rates have still increased. In light of Department of Health recommendations that women should exclusively breastfeed their babies for six months, rates of exclusive breastfeeding have been determined for the first time. This shows that only 65% of women exclusively breastfed even on day one. Of those women who exclusively breastfed on day one, over a third introduced formula by the end of the first week. The ways in which exclusive breastfeeding status was lost can be seen in Table 2. A worrying trend in the figures is the fast drop off in breastfeeding rates. By one week only 63% are breastfeeding at all, at six weeks this decreases to 45% breastfeeding and at six months only a quarter of mothers are still breastfeeding at all. Despite six months exclusive breastfeeding being recommended, less than 1% of infants were exclusively breastfed for this long. Given the sharp drop off in breastfeeding rates shortly after birth, perhaps the focus should be on supporting those women who start breastfeeding to continue with it, rather than focussing on increasing initiation rates as is the case at present.

The survey found 70% of women intended to at least partially breastfeed antenatally and almost 80% actually attempted to breastfeed following their baby’s birth. It therefore needs to be considered why so many women start breastfeeding, but give up within a few days or a few weeks. More needs to be done to improve families’ experience and success in breastfeeding. Women in the survey stayed on average 2 days in the hospital; including more than half of first time mothers. This means that most women went home before their milk came in and breastfeeding was established. It is well recognised that while rooting is an instinct, latching on is a skill that has to be learned by mother and baby; failing to learn these skills can compromise breastfeeding and lead to problems for mother and baby. Each mother-infant pair is unique and it cannot be assumed that if a mother breastfed successfully before that she will do so again. Undoubtedly some infants – for a variety of reasons – learn the skills necessary to latch on and suckle successfully more easily than others. Less than three quarters of women in the survey were shown how to put their baby to the breast in the first few days, although this was higher for first time mothers (89%). When women were asked how long an advisor stayed to help them, only 1 in 10 women reported that advisors stayed for the whole feed; most left once the baby was feeding, although some did come back to check on the mother and baby.

Evidence that breastfeeding skills may not be being taught effectively comes from the top three reasons given for giving up breastfeeding all of which may be related to poor positioning. Further evidence that women are being failed at present is that up to 9 in 10 of women who gave up breastfeeding in the first six weeks would have liked to have fed for longer. Effective ways of supporting women in successful initiation of breastfeeding have to be developed, particularly at a time when midwife numbers are falling and while the expectations placed on them in reports such as Maternity Matters²² are increasing. (see Table 2)

Around a third of breastfeeding mothers had experienced some kind of feeding problem in the first few weeks of their baby’s life.(see Table 3). The survey found that after the first few weeks (when the midwife was the top source of advice) most families’ tended to use the Health Visitor for advice on feeding problems.




Approximately a third consulted a doctor or GP; a similar percentage consulted family or friends. It is difficult to know how knowledgeable the average GP would be about breastfeeding and impossible to be sure of the quality of advice given by family or friends. Only very small numbers used a support group or specialist breastfeeding clinic. This is disappointing as a recent Cochrane systematic review²³ found that both professional and lay support were effective in prolonging breastfeeding; although there was a trend towards a combination of professional and lay support being most successful. The systematic review found that face to face interventions were more successful than telephone contacts. An anecdotal case report²⁴ suggested that antenatal classes should prepare women better for the actual experience of breastfeeding in the early days and focus more on practical issues rather than merely extolling the benefits. This mother – a 34 year old lawyer and the daughter of a paediatrician – also suggested that support should be provided at home postnatally, as some women may find it difficult to leave the home in the early days of parenthood.

How to support breastfeeding

· Follow the Ten Steps to Successful Breastfeeding (see Table 4)
· Where possible encourage skin to skin contact between mother and baby immediately after birth
· Encourage a first breastfeed within half an hour of birth
· Try to make sure a suitably trained person (lay or professional) observes at least one breastfeed before discharge to ensure that the baby is latching on correctly
· Encourage mothers not to go home until they are confident they can latch their baby on to the breast successfully
· Ensure as many staff as possible have attended training to allow them to confidently support breastfeeding mothers
· Promote the establishment and links with lay breastfeeding supporters; particularly those who can visit women at home
· Discourage breastfeeding mothers from giving any other food or fluids except breastmilk in the first few weeks.· Underline to mothers the importance of having enough to eat and drink and enough rest; encourage them to delegate as many tasks to others as they can in the early days.





Breastmilk – what about the alternatives?

The Department of Health recommends that exclusive breastfeeding is the best form of nutrition for babies for about the first six months of life. However, as has been demonstrated above, the reality falls far short of this idea and infant formula is currently the major source of nutrition for infants in the UK. It is therefore imperative that health professionals caring for babies and their families are knowledgeable about infant formulas so that they can provide accurate, up to date advice to families.

In the twenty first century, infant formula is not just the major source of calories, protein, vitamins and minerals. In effect, formula milk needs to be a ‘functional food’, that is a food or food ingredient that has been demonstrated to affect specific functions or systems in the body. Infant formula composition has evolved from trying to mimic breastmilk to trying to replicate specific biological effects of breastmilk. That is, it is recognised that infant formula is increasingly being formulated to provide some of the known benefits of breastmilk.

The first example of adding an ingredient to convey such benefits, was long chain polyunsaturated fatty acids (LCPs). These fatty acids are important for healthy phospholipid membrane function, particularly in neural tissue. In adults, LCPs are formed from the essential fatty acids linoleic acid (omega 6 series) and alpha-linolenic acid (omega 3 series). These are desaturated and elongated to form LCPs including arachidonic acid (AA) and docosahexaenoic acid (DHA). Towards the end of the 1980s, research began to show differences in cognitive development between breast fed and formula fed infants²⁵. It was hypothesised that long chain polyunsaturated fatty acids, present in breastmilk but not in infant formulas, were responsible. Lower serum levels were found in formula fed infants, leading to the hypothesis that endogenous synthesis from the precursors at birth is not sufficient, making AA and DHA conditionally essential in infancy. As a result, most infant formula companies have chosen to add LCPs – first to formulas for preterm infants where the differences in outcome were first seen – and then to term formulas also. However, two recent Cochrane reviews^26,27have failed to show significant differences for infants fed on supplemented formulas in term or preterm infants although the review concluded that more research needs to be carried out. Nucleotides are proteins present in breastmilk, which form the basis for DNA and RNA, the building blocks of genetic material. In addition, they are important in immune function, lipid metabolism and the rapid growth of the gut in infancy. Demand for nucleotides is greatest during times of rapid growth and it is possible that demand may exceed the infant’s capacity for supply at these times. It has been reported that the addition of nucleotides may reduce the risk of diarrhoea²⁸ in infants and may help catch up growth in small for gestational age infants²⁹. Nucleotides are now added to most infant formulas.

The acknowledgement of the importance of gut health for overall well-being in all age groups, has led to interest in the role of probiotics and prebiotics in many areas of health, including infant feeding:

• Probiotics are strains of bacteria which are beneficial to gut health and include Lactobacilli and Bidfidobacteria strains; in breastfed infants bidfidobacteria dominate. Supplements (such as drinks, yogurt or in capsules) can top up the body’s supply and help protect against pathogens.
• Prebiotics are oligosaccharides, such as inulin, fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS). These non-digestible carbohydrates are resistant to the body’s digestive enzymes and reach the colon largely intact. They selectively encourage the growth and activity of beneficial bacteria. Prebiotic oligosaccharides are present in breastmilk and are added to some infant formulas (Aptamil and Cow & Gate)

Breast and formula fed infants are known to have different gut flora populations; adding prebiotics to infant formula has been suggested to result in stool cultures and consistency closer to those of breastfed babies both in term³⁰ and preterm³¹ infants. As a result, some infant formula manufacturers such as Aptamil and Cow & Gate are now adding prebiotics to their infant formulas. Much research is currently being undertaken on the potential benefits of pro-and prebiotics for infant health; expected benefits include a reduction in infection rates as well as a reduced allergic response. One study has a shown a reduction in the incidence of eczema in high risk babies fed a formula containing prebiotics³² and research continues.

Unsuitable milks for babies

1. Cows’ milk – may be used in weaning foods from six months, but should not be given as a main drink until at least one year. The main disadvantage is the low level of iron, which is important as iron deficiency anaemia is common in toddlers. Semi-skimmed milk should not be used before two years and skimmed milk not before five years, as full fat milk is a valuable source of calories and fat soluble vitamins for young children.
2. Goats’ milk – one follow on formula is available based on goats’ milk protein; the infant formula version has been removed from the market as infant formula regulations do not permit the use of goats’ milk as a source of protein for babies. Goats’ milk based products do not have any advantages over cows’ milk protein in terms of tolerance or allergy protection.
3. Soya formulas – these are not recommended for use in infancy – particularly under six months – because of potential concerns over fertility problems in both sexes later in life. However, they may be used if babies will not take a more suitable formula, by vegan infants if mothers do not breastfeed, or where other formulas may be contraindicated (e.g. galactosaemia).

In conclusion

Human breastmilk is a highly complex fluid, which almost certainly contains factors yet to be discovered. It is undoubtedly the best nutritional start to life for infants and healthcare professionals have a responsibility not only to highlight the nutritional benefits to parents, but to ensure that the necessary support is in place, so that a mother will have the skills and confidence to make breastfeeding a positive experience for both her and her infant. Health professionals, however, also have a responsibility to remain up to date with the rapidly changing science of infant nutrition and infant formula composition, so that they can advise appropriately if families choose to use infant formula.

* Current weight charts in the UK are mostly based on formula fed infants, as, after about the first six weeks of life, formula feeding is more common than breastfeeding. The World Health Organisation has recently published growth charts based on breastfed infants in six populations worldwide. There is a growing body of opinion that breastfed growth rates should be used as the ‘gold standard’ for all infants33. It is argued that this would prevent artificially high growth rates being seen as ‘normal’ and that slower growth rates would reduce morbidity in later life. A recent report by the Scientific Advisory Committee on Nutrition (SACN) and Royal College of Paediatrics and Child Health (RCPCH) recommended the use of these charts between 2 weeks and 2 years of life34. These recommendations were accepted by the Department of Health and the new charts are to be trialled in some areas of the UK35.

About the author

Kate Harrod-Wild BSc (Hons) RD
Paediatric Dietitian
Opinions expressed by the author are not neccessarily those or the publisher or editorial staff

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