Below is a selection of recent research on the effects of breastfeeding and breastmilk on neonatal outcomes. For more information on embedding Baby Friendly care in the neonatal unit, see our dedicated guidance document.
Parents as partners in care: Lessons from the Baby Friendly Initiative in Exeter
In this article we hear from Royal Devon and Exeter, the first neonatal unit to achieve full Baby Friendly accreditation, about their experience of implementing the standards and the difference they’ve made to vulnerable babies and their families. They highlight the importance of welcoming parents onto the unit, not as visitors but as central partners in their baby’s care – and the tough decisions that neonatal teams have to make to create this welcoming culture. Giving parents every opportunity to touch, care for and make decisions about their baby’s care can have profoundly positive effects on the baby’s development and family relationship building, both during their stay on the unit and beyond.
Read, K, and Rattenbury, L (2018). Parents as partners in care: Lessons from the Baby Friendly Initiative in Exeter, Journal of Neonatal Nursing,https://doi.org/10.1016/j.jnn.2017.11.006
Personalization of the Microbiota of Donor Human Milk with Mother’s Own Milk
This study explored whether donor breastmilk (DBM) could be inoculated with mother’s own breastmilk (MOM) from mothers of preterm babies to restore the live microbiota. Microbiome analyses indicated that each mother has a unique microbiota and that live microbial reestablishment of DBM may provide these microbes to individual mothers’ infants. The agreement between the results obtained from the viable bacterial counts and the microbiome analyses indicate that DBM incubated with 10–30% v/v of the MOM for 4 h is a reasonable restoration strategy. Although further studies are required to establish efficacy and safety, the findings may have implications for the value of DBM to the health and life chances of preterm babies when MOM is not available. Find out more about donor milk in our guest blog from Hearts Milk Bank.
Cacho, N, et al (2017), Personalization of the Microbiota of Donor Human Milk with Mother’s Own Milk. Frontiers in Microbiology, doi: 10.3389/fmicb.2017.01470
The Dual Nature of Early-Life Experience on Somatosensory Processing in the Human Infant Brain
This study explored how early-life experiences of touch in the neonatal unit affect preterm infants’ sensory development, measured by the strength of infants’ brain response to gentle touch at discharge home. The researchers found that supportive experiences of touch (e.g., breastfeeding, skin-to-skin contact) were associated with stronger brain responses to gentle touch upon discharge, similar to the responses of full term babies. Painful experiences, on the other hand, (e.g., skin punctures, tube insertions) were associated with reduced brain responses to gentle touch at discharge. The results have important implications for neonatal care and the impact this has on brain development.
Maitre, N, et al (2017), The Dual Nature of Early-Life Experience on Somatosensory Processing in the Human Infant Brain. Current Biology, DOI: http://dx.doi.org/10.1016/j.cub.2017.02.036
A Comparison of Breast Milk and Sucrose in Reducing Neonatal Pain During Eye Exam for Retinopathy of Prematurity (ROP)
This study found that both breastmilk and sucrose reduced the Premature Infant Pain Profile (PIPP) score for infants undergoing ROP examinations, and that the preterm infants in the breastmilk group recovered and returned to their initial values more quickly after the ROP examination than the infants in the sucrose group.
Taplak, A S, and Erdem, E (2017), A Comparison of Breast Milk and Sucrose in Reducing Neonatal Pain During Eye Exam for Retinopathy of Prematurity. Breastfeeding Medicine doi/full/10.1089/bfm.2016.0122
Kangaroo mother care for preterm infants
A 20 year follow-up study of the impact of kangaroo care (KMC, or skin-to-skin contact) on preterm and low birthweight babies found significant, long-lasting social and behavioural protective effects even 20 years after the intervention. The effects of KMC at one year on IQ and home environment were still present 20 years later in the most fragile individuals, reflected by reduced school absenteeism and reduced hyperactivity, aggressiveness, externalization, and socio-deviant conduct of young adults. Neuroimaging showed larger volume of the left caudate nucleus in the KMC group.
Charpak, N (2016), Twenty-year Follow-up of Kangaroo Mother Care Versus Traditional Care. Pediatrics 139(1):e20162063
Breastmilk Feeding, Brain Development, and Neurocognitive Outcomes: A 7-Year Longitudinal Study in Infants Born at Less Than 30 Weeks’ Gestation
This study of 180 infants born at less than 30 weeks’ gestation found that predominant breastmilk feeding in the first 28 days of life was associated with a greater deep nuclear gray matter volume at term equivalent age and better IQ, academic achievement, working memory, and motor function at 7 years of age.
Belfort, M B, et al (2016) Breast Milk Feeding, Brain Development, and Neurocognitive Outcomes: A 7-Year Longitudinal Study in Infants Born at Less Than 30 Weeks’ Gestation. The Journal of Pediatrics, Vol 177, pp 133–139 dx.doi.org/10.1016/j.jpeds.2016.06.045
“Giving us hope”: Parent and neonatal staff views and expectations of a planned family- centred discharge process
This study of discharge processes from neonatal units revealed the positive impact of the ‘Train to Home’ approach. This family-centred process facilitates staff-parent communication, encouraging parent involvement in care, an understanding of their baby’s needs and providing a realistic estimated discharge date. The approach was welcomed by parents and staff, and helped parents to feel more confident and prepared for their baby’s discharge home.
Ingram, J, et al (2016) “Giving us hope”: Parent and neonatal staff views and expectations of a planned family- centred discharge process (Train to Home). Health Expectations, doi:10.1111/hex.12514
Differences in enteral feeding practices – An international survey
A web-based survey of 127 tertiary neonatal intensive care units in a variety of countries across the world was carried out to evaluate enteral feeding practices. When asked about initiating enteral feeding within the first 24 hours of life the proportion of units doing this was: 35% if gestational age (GA) <25 weeks, 43% if GA 25–27 weeks and 71% if GA 28–31 weeks. In general, Scandinavian units introduced enteral feeds the earliest, followed by UK/Ireland.Continuous feeding was routinely used for infants below 28 weeks’ gestation in almost half of the Scandinavian units and in approximately one sixth of units in UK/Ireland, but rarely in Australia/New Zealand and Canada. Minimal enteral feeding for 4–5 days was common in Canada, but rare in Scandinavia. Target enteral feeding volume in a ‘stable’ preterm infant was 140–160ml/kg/day in most Canadian units and 161–180ml/kg/day or higher in units in the other regions. There were also marked regional differences in criteria for use and timing when human milk fortifier was added. The authors concluded that there are significant areas of uncertainty and marked variability in feeding practices.
Klingenberg C, Embleton ND, Jacobs SE et al (2011) Enteral feeding practices in very preterm infants: an international survey. Arch. Dis. Child. Fetal Neonatal Ed. 10.1136/adc.2010.204123
Enhanced staff contact for breastfeeding mothers of low birth weight infants is cost effective
This study evaluated the cost-effectiveness of enhanced staff contact for mothers with infants in a neonatal unit with a birth weight of 500g-2.5kg in the UK. There is evidence that breastmilk feeding reduces mortality and short and long-term morbidity among infants born too soon or too small. The study population was divided into three groups by weight: 500-999g, 1kg-1.749kg, and 1,75kg-2,5kg. The measure of benefit was quality-adjusted life-years. The researchers found that the intervention was less costly and more effective than the comparator for each birth weight group. They acknowledge that whilst the results provide preliminary indications that enhanced staff contact may be cost-effective, this is the first economic evaluation in this complex field and further work is indicated. Their findings offer a model to be developed in future research.
Rice SJ, Craig D, McCormick F et al (2010) Economic evaluation of enhanced staff contact for the promotion of breastfeeding for low birth weight infants. Int J Technol Assess Health Care ;26(2): 133.
Breastfeeding promotion for infants in neonatal units
It is known that when babies are born preterm or are sick, the use of breastmilk substitutes is associated with increased adverse outcomes both in the short and long term. A major systematic review and economic analysis has been conducted to evaluate the effectiveness and cost-effectiveness of interventions that promote or inhibit breastfeeding (or feeding with breastmilk) for infants admitted to neonatal units. The authors found that kangaroo skin-to-skin contact, peer support, simultaneous breast milk pumping, multidisciplinary staff training and the Baby Friendly accreditation of the maternity unit have been shown to be effective, whilst skilled support from trained staff in hospital has been shown to be potentially cost-effective.
They conclude that many of these interventions inter-relate and are unlikely to be effective if used alone, particularly in the absence of staff training or where the environment is not encouraging and supportive to breastfeeding and expressing breastmilk and where mothers are not afforded close contact with their infants. In Baby Friendly accredited units the numbers of infants receiving any breastmilk in the first week of enteral feeds, and the duration of any or exclusive breastfeeding, are significantly increased. The authors call for a consistent strategy to promote breastfeeding/breastmilk feeding in neonatal units as without such a strategy at national and unit levels, the combination of a stressful environment and lack of skills needed to support mothers of these vulnerable infants is likely to result in inconsistent and ineffective care.
Renfrew M, Craig D, Dyson L et al (2009) Breastfeeding promotion for infants in neonatal units: a systematic review and economic analysis. Health Technol Assess 13(40)
Breastfeeding may help earlier discharge for preterm infants
Moderately preterm infants (30-34 weeks) account for a large proportion of admissions and bed-days in neonatal units. A large study (2,388 infants) of the postmenstrual age (PMA) at hospital discharge and its relationship to perinatal risk factors and to organisation of care was carried out in Sweden. The researchers found that average PMA at discharge was 36.9 weeks. High (35 years) maternal age, multiple birth, small for gestational age, respiratory distress syndrome, infection, hypoglycaemia and hyperbilirubinaemia were significantly associated with higher PMA at discharge, but could only explain 13 per cent of the differences. Breastfed infants had lower PMA at discharge (mean 2.7 days lower) than those not breastfed, partly explained by lower morbidity in the breastfed infants and the researchers recommend that supporting the establishment of successful breast feeding in preterm infants should therefore be given high priority in neonatal care.
Altman M, Vanpee M, Cnattingius S et al (2009) Moderately preterm infants and determinants of length of hospital stay. Arch. Dis. Child. Fetal Neonatal Ed; 94: F414-F418
The management of late preterm infants
Infants born between 34 and 36+6 weeks’ gestation are often the size and weight of term infants. Therefore, parents, caregivers and health-care professionals may treat late-preterm infants as though they are developmentally more mature than they are. This paper identifies the increasing incidence of babies born at this gestation and proposes management plans for their care.
Engle WA, Tomashek KM, Wallman C and the Committee on Fetus and Newborn (2007) “Late-preterm” infants: A population at risk. Pediatrics; 120 (6): 390-1401
WHO review of optimal feeding of low-birth-weight infants
A review of the current evidence regarding the feeding of low birth weight infants (i.e. below 2,500g) has been published and confirms the following:
- Breastfeeding, or feeding with mother’s own expressed breastmilk, is the best option for all such babies.
- Where this is unavailable, donor human milk would be the next best choice.
- Where neither is available, infants of <32 weeks gestation should receive pre-term infant formula.
- The timing of the introduction of solid diet should generally equate with that for babies born at term.
- Supplementation of breastmilk with calcium and phosphorus is recommended for babies with birth weight <1500g.
- Expressed breast milk should be offered by cup rather than bottle as this leads to higher rates of exclusive breastfeeding at discharge from hospital.
- Non- nutritive sucking has some benefits in terms of reduced hospital stay. Encouraging sucking on the ‘emptied’ breast, after expression of breast milk, may result in improved breastfeeding rates at discharge and at follow-up.
- Kangaroo mother care is recommended in clinically stable infants <2000g.
- Use of medications such as domperidone may help improve milk supply.
Edmond K, Bahl R (2007) Optimal feeding of low-birth-weight infants: technical review. WHO
Donor breastmilk versus infant formula for preterm infants
It is recognised that the health of preterm babies benefits greatly from the ingestion of their mothers own breastmilk due to a number of factors including the presence of active enzymes that enhance the maturation of the underdeveloped gut, anti-infective properties which protect the newborn from infection and earlier tolerance of full enteral feeding. As donor milk is usually provided by women who deliver at term, and is pasteurised, the authors argue that it cannot be presumed that it will have the same effect as mothers’ own breastmilk. The aim of this systematic review, therefore, was to compare the effects of pasteurised donor breast milk and infant formula in preterm infants.
Seven studies were found to comply with the inclusion criteria, although methodological weaknesses were present in all. Six looked at the impact of donor breastmilk on necrotizing entero-colitis (NEC) and the combined evidence from these studies suggests that donor milk reduces the risk of NEC by about 79%. The other main outcome measure of growth had mixed findings with more studies finding in favour of formula in terms of infant growth. One study however, tracked growth at 9 and 18 months and 7-8 years at which times no significant differences in a range of growth measurements were found. Importantly, this study found significantly slower growth in the donor milk group compared with the formula group during the early postnatal period. The authors suggest that further research is needed to confirm their findings and measure the effect of donor breast milk that is fortified or given as a supplement to mother’s own milk.
In response to the Boyd paper (above) Williams et al make a number of useful comments in a perspective published in the same journal.
- Given the incidence of preterm birth, the paucity of data in this area is disappointing. Despite this Boyd et al were able to clearly demonstrate that formula-fed very low birthweight babies are at significantly increased risk of necrotising enterocolitis (NEC) compared with those fed exclusively on breast milk.
- The ongoing high incidence of NEC and related mortality and severity of morbidity among survivors make this finding important. The recent eleventh annual report of the British Paediatric Surveillance Unit cited an incidence of 2.1/1000 neonatal unit admissions, 65% of whom weighed under 1500 g at birth. Overall mortality was 22% but it was significantly lower in those fed human milk compared with those fed on formula (5% v 26%, p<0.05).
- Remarkably, despite large differences in early rates of growth seen in the neonatal unit, no anthropometric differences were observed at school age, even in the group fed donor breast milk as sole diet.¹
- They recommend setting up a national network of milk banks as this would enable greater cost-effectiveness and quality control together with affording the opportunity for further research into this important area.
¹ Morley R, Lucas A. Randomised diet in the neonatal period and growth performance until 7.5–8 y of age in preterm children. Am J Clin Nutr 2000;71:822–8.
Boyd C.A., Quigley M.A., Brocklehurst P (2007) Donor breast milk versus infant formula for preterm infants: systematic review and meta-analysis. Archives of Disease in Childhood; 92:F169-F175
Williams A.F., Kingdon C.C., Weaver G (2007) Banking for the future: investing in human milk . Archives of Disease in Childhood; 92:F158-159
There has been significant reliable evidence produced over recent years to show that breastfeeding is a major contributor to public health and has an important role to play in reducing health inequalities even in the industrialised countries of the world. Baby Friendly provides an overview of recent studies relevant to the health benefits and management of breastfeeding.Search through the categories below, or use the search button (🔍 icon, top right of the screen) to search by keyword.Please note, this is not a comprehensive list, but rather contains the studies that we have found to be most pertinent. For details of more research, see The evidence and rationale for the Unicef UK Baby Friendly Initiative standards or sign up to our regular research and news mailings.
When reading these papers it is important to consider the methodology, sample sizes, response rates and reported findings to determine their relevance. Where systematic reviews or meta-analyses are available, allowing analysis of findings from a number of well-selected studies, these obviously provide a stronger evidence base on which it is possible to base arguments with greater conviction.
It is always important to bear in mind the following when considering the strength of any evidence:
- Carrying out randomised controlled trials which are clearly recognised as the “gold standard” is not always possible as it is not ethical to randomly allocate mothers in a way which arbitrarily may decide that half of the group will bottle feed.
- Many studies are flawed by staff or mothers deviating from the protocol as this may seem counter-intuitive or too hard to follow in the situation in which they are being cared for or living.
- Sample sizes, particularly for older infants, become very small, particularly in countries such as the UK with low breastfeeding continuation rates/exclusivity. It is therefore difficult to accurately infer statistics.
- In specialist areas such as caring for preterm infants, it is difficult to recruit mothers at such difficult times and again, small numbers are reflected in a lack of solid evidence about many aspects of care.
- Breastfeeding may be documented as having a “small protective effect” against certain illnesses. Whilst it is clearly accurate to say that that the risk of not breastfeeding is greater with some conditions than others, what is a small protective effect in one child is likely to have a much more dramatic effect across a whole population.