Infant health research: Meta-Analyses

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The studies below explore the wide-reaching, long-term impact of infant feeding choices, particularly the huge benefits that breastfeeding brings to physical and emotional well-being, as well as the dangers of failing to support breastfeeding.

National Maternity and Perinatal Audit: Organisational report 2017

The National Maternity and Perinatal Audit’s first report provides a detailed snapshot of NHS maternity services across England, Scotland and Wales, Overall the report found wide variations in terms of staffing and services available, with no “typical” maternity unit to point to, and many maternity services feeling that they did not offer continuity of carer. Worryingly, in 2015/16, 27% of alongside midwife-led units and 23% of freestanding midwife-led units closed at least once due to lack of staff or beds. The findings will be used to help benchmark services against national standards, identify good practice and areas for improvement in the care of women and babies.

http://www.maternityaudit.org.uk/pages/home

Term admissions to neonatal units in England: a role for transitional care? A retrospective cohort study

This study sought to identify the primary reasons for term admissions to neonatal units in England, to determine risk factors for admissions for jaundice and to estimate the proportion who can be cared for in a transitional setting without separation of mother and baby. Researchers found that respiratory disease was the most common reason for admission overall, although jaundice was the most common reason for admission from home (22% home vs 5% hospital). Risk factors for admission for jaundice include male, born at 37 weeks gestation, Asian ethnicity and multiple birth. The majority of babies received only a brief period of phototherapy, and only a third received intravenous fluids, suggesting that around two-thirds of term admissions for jaundice may be appropriately managed in a transitional care setting, avoiding separation of mother and baby. They suggested that babies with risk factors may benefit from a community midwife postnatal visit around the third day of life to enable early referral if necessary.

Batterbsy, C. et al (2017) Term admissions to neonatal units in England: a role for transitional care? A retrospective cohort study BMJ Open 2017;7:e016050. doi: 10.1136/bmjopen-2017-016050

Avoiding Term Admissions in Neonatal Units (ATAIN programme)

NHS Improvement has launched a new resource for health professionals aimed at reducing avoidable admission of full-term babies into neonatal units. It found that up to   30% of neonatal unit admissions between 2011 and 2013 were potentially avoidable. In line with our neonatal standards, it highlights the importance of keeping babies and mothers together wherever possible to protect both child and maternal health. The resource looks both at avoiding harm requiring admission, as well as considering opportunities to care for babies in an alternative setting to keep them with their mothers. It includes guidance on earlier detection of jaundice, identification of “at risk” babies and the importance of skin-to-skin contact for a baby’s longer-term health outcomes.

https://improvement.nhs.uk/resources/preventing-avoidable-admissions-full-term-babies/

Early additional food and fluids for healthy breastfed full-term infants

This Cochrane review exploring the impact of introducing foods and fluids in addition to breastmilk before the recommended age of 6 months supported the current recommendation of the World Health Organization that, as a general policy, exclusive breastfeeding, without additional foods or fluids, should be recommended for the first 6 months after birth. Care should be taken to provide skilled support from birth to establish milk production and effective milk transfer and to protect infants from additional fluids or foods if these are not clinically indicated.

Smith, H, et al (2016) Early additional food and fluids for healthy breastfed full-term infants. Cochrane Database of Systematic Reviews 2016, Issue 8. Art. No.: CD006462. DOI: 10.1002/14651858.CD006462.pub4

Suboptimal breastfeeding in the United States: Maternal and pediatric health outcomes and costs

This study into the impact of suboptimal breastfeeding in the United States found annual excess deaths attributable to suboptimal breastfeeding totalled 3,340, 78% of which were maternal due to myocardial infarction, breast cancer and diabetes. Excess pediatric deaths totalled 721, mostly due to Sudden Infant Death Syndrome (SIDS) and necrotizing enterocolitis (NEC). Researchers found that for every 597 women who optimally breastfeed, one maternal or child death was prevented. They noted that breastfeeding has a larger impact on women’s health than previously appreciated, and that policies to increase optimal breastfeeding could result in substantial public health gains.

Bartick, M, et al (2017) Suboptimal breastfeeding in the United States: Maternal and pediatric health outcomes and costs. Maternal & Child Nutrition, Vol 13, Issue 1, DOI: 10.1111/mcn.12366

The Lancet breastfeeding series

This powerful series presents resounding evidence that breastfeeding protects health, saves lives and cuts costs in every country worldwide. It finds that women are not getting the support they need to breastfeed, and that breastfeeding success is the collective responsibility of society. It demonstrates that the Baby Friendly Initiative is highly effective in improving breastfeeding practices, and that increasing breastfeeding worldwide could prevent over 800,000 child deaths every year.

The Lancet (2016): Increasing breastfeeding worldwide could prevent over 800,000 child deaths every year

Special issue on the impact of breastfeeding

This supplement to Acta Paediatrica (coordinated by the World Health Organisation and funded by the Gates Foundation) presents a series of meta-analyses and systematic literature reviews examining a variety of health effects potentially related to breastfeeding.

Acta Paediatrica, Special Issue (2015): Impact of Breastfeeding on Maternal and Child Health

Long-term consequences of breastfeeding on cholesterol, obesity, systolic blood pressure and type 2 diabetes

This study systematically reviewed the evidence on the associations between breastfeeding and overweight/obesity, blood pressure, total cholesterol and type 2 diabetes. It was found that breastfeeding decreased the odds of type 2 diabetes and based on high-quality studies, decreased by 13% the odds of overweight/obesity. No associations were found for total cholesterol or blood pressure.

Horta, B.L. et al (2015). Long-term consequences of breastfeeding on cholesterol, obesity, systolic blood pressure and type 2 diabetes: a systematic review and meta-analysis. Acta Paediatrica, Special Issue: Impact of Breastfeeding on Maternal and Child Health. Volume 104, Issue Supplement S467, pages 30-37.

Breastfeeding and reduced hospital admissions

The Department of Health’s infant feeding profiles 2010-11 demonstrated a correlation between higher rates of breastfeeding and lower rates of inpatient admissions for infants under 1 year. They explore the impact of breastfeeding on a range of conditions, including ear infections and asthma.

Department of Health (2013). Infant feeding profiles 2010 to 2011.

The effects of breastfeeding on children, mothers and employers

This research project funded by the Economic and Social Research Council and conducted by the Institute of Social and Economic Research (ISER)  explored the impact of breastfeeding, focusing on four main areas: The Success Story of the Unicef UK Baby Friendly Initiative; breastfeeding and infant hospitalisations for infections; breastfeeding and socio-emotional development and breastfeeding and cognitive development. Collectively, the results from ISER’s research point to the existence of some positive breastfeeding effects independent from other influencing factors such as social class or parents’ education. These results show that breastfeeding may well have a significant part to play in the Government’s efforts to reduce inequality. The research also showed that the extent of time a child was breastfed was an important element in identifying a causal relationship between better child outcomes and breastfeeding – “It could be that only prolonged and exclusive breastfeeding (four months or longer) offers a substantial level of benefit.” This reiterates the importance of support for women to continue to breastfeed exclusively for longer.

https://www.iser.essex.ac.uk/research/projects/breastfeeding 

The burden of suboptimal breastfeeding

This US study updated research from 2001 revealing that $3.6 billion could be saved if breastfeeding rates were increased. It studied 3 diseases and totaled direct and indirect costs and cost of premature death. This study used current breastfeeding rates and added additional diseases analyzed in the 2007 breastfeeding report from the Agency for Healthcare Research and Quality. It was found that if 90% of US families could comply with medical recommendations to breastfeed exclusively for 6 months, the United States would save $13 billion per year and prevent an excess 911 deaths, nearly all of which would be in infants ($10.5 billion and 741 deaths at 80% compliance).

Bartick, M. & Reinhold, A. (2010) The Burden of Suboptimal Breastfeeding in the United States: A Pediatric Cost Analysis. Pediatrics, 125/5

Evidence on the long-term effects of breastfeeding: To establish the impact of long term breastfeeding, the World Health Organization commissioned a review of the evidence available in the form of a series of systematic reviews. The available evidence suggests that breastfeeding may have long-term benefits. Subjects who were breastfed experienced lower mean blood pressure and total cholesterol, as well as higher performance in intelligence tests. Furthermore, the prevalence of overweight/obesity and type-2 diabetes was lower among breastfed subjects.

Horta B.L. et al (2007) Evidence on the long-term effects of breastfeeding. WHO

Breastfeeding and health outcomes in developed countries: A review from the USA investigated the effects of breastfeeding in developed countries. The reviewers concluded that a history of breastfeeding was associated with a reduction in the risk of acute otitis media, non-specific gastroenteritis, severe lower respiratory tract infections, atopic dermatitis, asthma (young children), obesity, type 1 and 2 diabetes, childhood leukaemia, sudden infant death syndrome (SIDS), and necrotizing enterocolitis (NEC). For maternal outcomes, a history of lactation was associated with a reduced risk of type 2 diabetes, breast, and ovarian cancer. Early cessation of breastfeeding or not breastfeeding was associated with an increased risk of maternal postpartum depression.

Ip S et al (2007) Breastfeeding and Maternal Health Outcomes in Developed Countries. AHRQ Publication No. 07-E007. Rockville, MD: Agency for Healthcare Research and Quality

Impact of breastfeeding on long-term child health: This US study looked at data collected between 1986 and 2010, to find associations between breastfeeding and long term health and behavioural outcomes. Data was analysed from a full data set of 11,504 children aged 4 to 14, and a smaller sub-set of  1,773 sibling pairs where one infant had been breastfed and the other formula fed.

Results for the full data set suggested that children who were breast- as opposed to formula fed did significantly better in 10 of 11 outcomes studied (BMI, obesity, asthma, hyperactivity, parental attachment, reading, vocabulary, maths, memory skills, academic performance). When analysis was restricted to the smaller data set of sibling pairs, no difference was seen in 10 of the 11 outcomes and breastfed children were reported to be more likely to have asthma than the formula fed infants.

Key points to consider:

  • The Department of Health and the World Health Organisation recommend that infants are exclusively breastfed for around six months and thereafter for 2 years alongside other foods. The amount of breastmilk an infant receives has been shown to impact on the health and wellbeing outcomes for both the mother and the infant. From reading this study it is not possible to estimate how much breastmilk the siblings received or for how long they were exclusively breastfed. This is particularly significant because, as the authors point out, feeding practices in the US changed significantly over the 24 year study period. Without this data, it could be argued that any results should be treated with extreme caution. For more information on the available body of evidence, please see our Evidence document.
  • Data collection on breastfeeding and other variables, in some cases was retrospective and relied on mothers’ recall sometime after the event, rather than by observation.
  • The study did not look at outcomes for allergies, immune status and diabetes (where previously, breastfeeding has been shown to improve outcomes), neither did it look at health outcomes for mothers.
  • The conclusion highlights the need in the US to improve parental leave, flexible working and good quality child care for mothers.
  • In the UK, The Advisory, Conciliation and Arbitration Service (ACAS), the Government’s employment advice service, has published new guidance for employers on supporting breastfeeding upon a mother’s return to work.

Several reviews and comment pieces have been written on this study:

NHS Choices

Breastfeeding Medicine

The Lonely Scribe

Original study: Colen, C.G., Ramey, D.M., Is Breast Truly Best? Estimating the Effects of Breastfeeding on Long-term Child Health and Wellbeing in the United States Using Sibling Comparisons, Social Science & Medicine (2014), doi: 10.1016/j.socscimed.2014.01.027.