Neonatal Care Research
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.
Breastfeeding promotes early neonatal regulatory T-cell expansion and immune tolerance of non-inherited maternal antigens
Cardiac Performance in the First Year of Age Among Preterm Infants Fed Maternal Breast Milk
Preterm infants with higher consumption of mother’s own milk were found to have enhanced cardiac performance at age 1 year, suggesting that mother’s own milk consumption may play a dynamic modulator role on cardiac mechanics in preterm-born infants. This cross-sectional study of cardiac and nutritional data included 80 individuals born preterm and 100 individuals in the control group born full-term born between 2011 and 2013.
Neonatal health care providers can support lactation in the NICU and potentially reduce disparities in the provision of mother’s own milk by encouraging early and frequent milk expression and by promoting skin-to-skin contact and direct breastfeeding. Mother’s own milk is the optimal nutrition source for very low birth weight babies (≤1500 g), providing short- and long-term health benefits.
Parker, M. et al. 2020. Promoting Human Milk and Breastfeeding for the Very Low Birth Weight Infant.
Is preterm donor milk better than preterm formula for very-low-birth-weight infants?
This single-centre prospective cohort study explored the effects of donor milk and preterm formula on growth, feeding tolerance and severe morbidity in 304 very-low-birth-weight infants. Results indicate that preterm donor milk does not affect growth in preterm infants, however it does significantly reduce feeding intolerance, helps to achieve full enteral feeding early, and lowers infection rates.
Variation in Oxygen Saturation by Pulse Oximetry During and After Breastfeeding Among Healthy Term Neonates During Early Postnatal Life at Tertiary Care Hospital
Variations in oxygen saturation levels of 60 healthy term infants were found to be significantly higher after breastfeeding, highlighting the crucial role effective breastfeeding plays in infant growth. Greater research is needed on infant breathing and sucking patterns to enable healthcare professionals to identify feeding difficulties and suggest effective breastfeeding methods.
Locked out: the impact of Covid-19 on neonatal care
Findings from a survey of 70 NHS Trusts and over 500 parents of neonatal babies born between March 2020 and February 2021 indicate ongoing challenges faced by parents in spending time with their infants in the critical first days and weeks of life. This has a negative impact on bonding, attachment, and parental mental health, with parents 70% more likely to say they found it difficult to bond with their baby if Covid-19 had resulted in restricted access to the neonatal unit.
Bliss. 2021. Locked out: the impact of Covid-19 on neonatal care
Intervention Strategies for the Poor Feeder in the Newborn Intensive Care Unit: External Pacing versus Imposed Regulation
This article compares and contrasts external pacing, a method of feeding developed in the 1980s as a cue-based technique to aid infants who were experiencing discomfort or distress – and imposed regulation – a diagnostic-based intervention strategy developed in the 1990s and implemented following a diagnosis of a disorganised suck on the Neonatal Oral-Motor Assessment Scale (NOMAS®).
Nurturescience versus neuroscience: A case for rethinking perinatal mother–infant behaviors and relationship
With the understanding that there has not been a significant improvement in the outcomes for babies who were separated from their mothers due to prematurity or birth defects in the past two decades, and that current neuroscience-based theories and treatment paradigms have not yet generated explanatory mechanisms that work, or provided testable hypotheses, a new field of scientific investigation titled “nurturescience” is proposed in this article, described as being drawn from biology, anthropology, sociology, physiological, and clinical research, and based on the basic needs of all newborns, mothers and families. Key themes in this new field include that the mother–infant dyad should not be separated, skin-to-skin contact, and infant and family centered developmental care .
Neuroscience meets nurture: challenges of prematurity and the critical role of family-centred and developmental care as a key part of the neuroprotection care bundle
This review examines the developmental milestones of fetal brain development and how preterm birth can disrupt this trajectory. Authors review the common morbidities associated with premature birth, and outline a range of sustainable and effective non-medical, family-centred and developmental care strategies which have the potential to improve neurodevelopmental outcomes and which and need to be considered part of the future neuroprotection care bundle.
Positive Effects of Kangaroo Mother Care on Long-Term Breastfeeding Rates, Growth, and Neurodevelopment in Preterm Infants
This study investigates the impact of kangaroo mother care (KMC) on breastfeeding and health outcomes in Chinese preterm infants. A longitudinal randomised controlled study was conducted with 79 preterm infant-mother dyads. The KMC group (n = 36) was provided 2.5 hours/day KMC during the neonatal intensive care unit (NICU) hospitalization, while the control group (n = 43) received standard care. Infant’s feeding regimens and physical growth were documented daily at NICU. Physical growth and Neonatal Behavioral Neurological Assessment were measured at 40 weeks, 3 months, and 6 months of corrected age (CA). Breastfeeding outcomes were documented at 6 months of CA. Findings showed that the KMC infants received higher mothers’ milk proportion during hospitalisation, less feeding intolerance at discharge, and higher exclusive breastfeeding proportion at 6 months CA. They also had increased body weight and measurements at discharge, along with higher neurobehavioral scores. Authors concluded that longitudinal KMC effects are significant in promoting preterm infants’ breastfeeding outcomes, growth, and neurodevelopment. Early initiation of KMC practice is highly recommended to the parent-infant population in Chinese NICUs to promote breastfeeding and developmental outcomes.
The Economic Impact of Donor Milk in the Neonatal Intensive Care Unit
Researchers conducted a retrospective analysis of 319 infants with very low birth weight born before (January 2011-December 2012, mother’s own milk + formula, n = 150) and after (April 2013-March 2015, mother’s own milk + donor milk, n = 169) to assess the cost-effectiveness of mother’s own milk supplemented with donor milk vs mother’s own milk supplemented with formula for infants of very low birth weight in the neonatal intensive care unit (NICU). Results found that infants receiving mother’s own milk + donor milk had a lower incidence of necrotizing enterocolitis (NEC) than infants receiving mother’s own milk + formula (1.8% vs 6.0%, P = .048). Mother’s own milk + donor milk was associated with $15 555 lower costs per infant (P = .045) and saved $1812 per percentage point decrease in NEC incidence.
The stepwise assembly of the neonatal virome is modulated by breastfeeding
Whilst healthy human neonates typically do not have viruses at birth, they can quickly become colonised which can lead to gastrointestinal disorders. This takes place in distinct steps: early after birth, bacteria colonises the infant gut and by one month can lead to virus-like particles. By four months of life, these viruses can become more prominent. The findings of this study concur with other reports that breastmilk can provide protection against viral infections.
Preterm Infants Fed Cow’s Milk-Derived Fortifier Had Adverse Outcomes Despite a Base Diet of Only Mother’s Own Milk
This study re-analysed a 12-centre randomised trial that compared exclusive human milk feeding, including mother’s own milk, donor milk and human milk-derived fortifier versus a cow’s milk exposed group fed mother’s own milk, preterm formula and cow’s milk derived fortifier (CMDF). To allow for an isolated comparison of fortifier type and to evaluate rates of necrotizing entercolitis (NEC), severe morbidity index of NEC surgery or death and other outcomes, a subgroup analysis (n = 114) selecting only infants receiving 100% mother’s own milk plus fortification/fed no donor milk or preterm formula was conducted. The study concluded that available evidence points to an increase in adverse outcomes with CMDF, including NEC and severe morbidity comprising NEC surgery or death.
National, regional, and worldwide estimates of low birthweight in 2015, with trends from 2000: a systematic analysis
This study from the London School of Hygiene & Tropical Medicine, the World Health Organization (WHO) and UNICEF estimates that globally 20.5 million babies were born with a low birthweight in 2015 – around 1 in 7 babies. The findings show that the problem is substantial in both high and low income countries, and highlight the need for more action to help tackle the underlying causes of low birthweight as well as improve care for low birthweight babies and their families. In the UK, the Unicef UK Baby Friendly Initiative neonatal standards support units to empower parents to be active partners in their baby’s care, support the development of close and loving parent-infant relationships, and enable babies to receive breastmilk, which gives them vital protection against infection and supports their short and long-term health outcomes.
The effects of kangaroo mother care on the time to breastfeeding initiation among preterm and low birthweight infants: a meta-analysis of published studies
This review of studies found that preterm and low birthweight infants receiving a kangaroo mother care intervention initiated breastfeeding 2 days 14 h 24 min earlier than infants who received the “conventional” care of the radiant warmer/incubator method.
Reducing parental trauma and stress in neonatal intensive care: systematic review and meta-analysis of hospital interventions
This review of studies suggests that interventions designed to support parents on a neonatal unit can be successful in reducing parental distress – in particular, complementary/alternative medicine and family-centered instruction interventions each decreased distress symptoms, with fathers and mothers improving to similar extents. The authors recommend further research into the issue, and argue for the importance of developing psychosocial interventions that serve NICU parents at large, including fathers and parents of full-term infants.
National Neonatal Audit Programme (NNAP) report
NNAP’s 2018 report highlights that around 1 in 7 babies born each year in England, Scotland and Wales will require specialist neonatal care. This year the report includes new audit data requirements which support the Baby Friendly standards, focusing on parental partnership in care; separation of mother and baby; and the presence of parents on consultant ward rounds. It measures breastmilk feeding at discharge and recommends the Baby Friendly neonatal standards and the Bliss Baby Charter to support this.
https://www.rcpch.ac.uk/resources/national-neonatal-audit-programme-annual-report-2018-2017-data
The type of feeding at discharge of very preterm infants: Neonatal intensive care units policies and practices make a difference
This Portuguese study of 580 preterm infants found a higher incidence of exclusive breastmilk feeding at discharge from neonatal units which had designated staff members to support mothers who were breastfeeding, had higher numbers of admissions, and provided parents’ eating facilities. The findings highlight the important role that neonatal care practices play in feeding outcomes.
Parental experience of interaction with healthcare professionals during their infant’s stay in the neonatal intensive care unit
This study found that the issues parents found most important about their interactions with staff while on the neonatal unit were: context of infant admission; interprofessional consistency; communication to support parental autonomy, trust and expectations; and respect and humane touches on the unit.
Beyond necrotizing enterocolitis prevention: Improving outcomes with an exclusive human milk–based diet
This American study explored the impact of an exclusive human milk-based diet (HUM) compared with a bovine-based diet (BOV) of mother’s own milk fortified with bovine fortifier and/or preterm formula on the health of extremely premature infants. Researchers found that infants on the HUM diet had a significantly lower incidence of necrotising enterocolitis (NEC) and mortality, as well as a reduction in late-onset sepsis, retinopathy of prematurity (ROP), and bronchopulmonary dysplasia (BPD).
Breastfeeding and risk for ceasing in mothers of preterm infants—Long‐term follow‐up
This study in Sweden explored the factors influencing breastfeeding continuation rates among mothers who breastfed their preterm infants at discharge from neonatal intensive care units (NICUs). The researchers found that partial breastfeeding at discharge, low maternal educational level, and longer length of stay in the NICU increased the risk for ceasing breastfeeding during the first 12 months. The study also looked at the impact of proactive telephone support compared with reactive support offered following discharge from the NICU, finding no difference on exclusive breastfeeding at 8 weeks.
The impact of preterm infants’ continuous exposure to breast milk odour on stress parameters: A pilot study
This pilot study found that preterm infants exposed to breastmilk odour from their own mothers demonstrate a persistent decrease in saliva cortisol levels, which continues after termination of the intervention. This finding may suggest that exposure to own mothers’ breastmilk odour has a soothing effect on preterm infants. The authors suggest that further randomized controlled studies are needed to evaluate this simple, safe, and inexpensive intervention.
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.
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.
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.
Beyond necrotizing enterocolitis prevention: Improving outcomes with an exclusive human milk–based diet
This American study explored the impact of an exclusive human milk-based diet (HUM) compared with a bovine-based diet (BOV) of mother’s own milk fortified with bovine fortifier and/or preterm formula on the health of extremely premature infants. Researchers found that infants on the HUM diet had a significantly lower incidence of necrotising enterocolitis (NEC) and mortality, as well as a reduction in late-onset sepsis, retinopathy of prematurity (ROP), and bronchopulmonary dysplasia (BPD).
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.
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.
“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.
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.
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.
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.
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.
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.
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.