The picture looks ridiculous. Why does this seem so unnatural yet we feed babies this same product around the world. Granted they don’t drink it from the source as this man is but the liquid is in essence the same. As the saying goes, “Cow’s milk is for baby cows”. When you put it that way it helps put in context the question posed as the title of this post. Should we be surprised that the consumption of a milk meant for another species might have some side effects at a population level if fed to enough infants; especially those with fragile bowel due to prematurity or other high risk condition compromising blood flow to the gut.
The following piece was written by Kari Bonnar with contributions from Sharla Fast both Registered Dieticians in our NICUs. It has been recognized for some time now that the use of donor milk in our highest risk premature infants is associated with less NEC and based on a previous review of the evidence we have been using DBM for the past several years. What this post explores though is the potential for further benefit by taking the next step. That is to ask the question; what additional benefit may be gained by replacing all sources of Cow’s Milk protein in this population. I am delighted to present their review of the literature here as I am sure you will find it as informative and thought provoking as I have.
The health benefits of human milk for all infants, including those born extremely premature, have been increasingly recognized and published.1 The American Academy of Pediatrics policy statement on breastfeeding and the use of human milk recommends that all preterm infants receive human milk including donor human milk if mother’s own milk is unavailable.2 When compared with a diet of preterm formula, premature infants have improved feeding tolerance and a lower incidence of late onset sepsis and necrotizing enterocolitis (NEC) when fed their mothers’ own milk.3 For mothers of extremely premature infants, providing sufficient milk to meet their infant’s needs is a common challenge. Pasteurized donor human milk has been made available to this population in WRHA since 2011 as it has been found to be well tolerated and is also associated with a significantly lower incidence of NEC.4
However, as the sole nutritive substance, human milk does not meet the macronutrient and micronutrient requirements of preterm infants. Multi-nutrient fortifiers are required to provide additional protein, minerals and vitamins to ensure optimal nutrient intake and neurodevelopmental growth.5 Prolacta Bioscience has recently launched in Canada with their human milk-based fortifiers, which are gaining popularity due to the ongoing research and success with these products in the United States, Austria, and now Canada.6 It is a new and novel approach that is proving to be most beneficial in reducing neonatal morbidity and mortality rates.7
In infants fed an exclusive human milk diet, Sullivan et al. found a reduction in medical NEC of 50% and surgical NEC of almost 90% compared to a diet containing cow’s milk-based products.7 To date, there is no other intervention that has had such a marked effect on the incidence of NEC.8 Abrams et al. found that for every 10% increase in intake of anything other than an exclusive human milk diet, the risk of NEC increases by 11.8% and the risk of surgical NEC increases by 21%, both with a 95% confidence interval.9
Patel et al. found that for every dose increase of 10ml/kg/day of human milk over the first 28 days post birth, the odds of sepsis decreased by 19%.10 Further to this, they found that overall NICU costs were lowest in very low birth weight (VLBW) infants who received the highest daily dose of human milk. Similarly, Abrams et al. reported that for each 10% increase in the intake of other than exclusive human milk diet, there was an 18% increase in risk for sepsis.9 In addition to predisposing the infant to other morbidities in the preterm population, and subsequent neurodevelopmental disability, sepsis significantly increases NICU costs by 31%. This translates into higher societal and educational costs for VLBW infants who survive sepsis with neurodevelopmental disability.10 ,11
A reduction in the number of days on total parenteral nutrition (TPN) was found by Cristofalo at al. with the use of an exclusive human milk based diet, in addition to reduction in sepsis and NEC.12 These same findings have been documented by Ghandehari et al. which reflect that an exclusive human milk diet leads to improved feeding tolerance and therefore, a decrease in total TPN days.13 Given that TPN is often the cause of late onset sepsis, the reduction of TPN days is imperative and almost always translates into decreased length of stay.14 Abrams et al. found that duration of TPN was 8 days less in infants receiving a diet containing <10% cow’s milk-based protein versus ≥ 10%, another recognizable dose related finding.9
It is well documented that increased growth leads to a decreased incidence of cerebral palsy and poor neurodevelopmental scores at 18-22 months corrected age, therefore adequate growth (weight, head circumference and length) is crucial in this population.15 The study by Hair et al. followed a standardized feeding protocol with early and rapid advancement of fortification with donor human milk derived fortifier and found that growth standards were being met and resulted in a marked decrease in extrauterine growth restriction.14 Cristofalo et al. study also compared growth rates, which were found to be slightly slower in the human milk fortified versus cow’s milk fortified arm of this study. However, it was mentioned that the small differences could be prevented with further adjustments in fortifier to improve rates of growth, as shown by Hair et al.12, 14 Abrams et al. confirms in their findings that growth rates were similar among human milk-based and cow’s milk-based fortification.9 This is a popular area of ongoing research with many abstracts also showing adequate growth rates with use of human milk-based fortifiers.
In closing, the review of current evidence clearly indicates that a diet of exclusive human milk is associated with lower mortality and morbidity in extremely premature infants without compromising growth and should be considered as an approach to nutritional care for these infants. Further research is needed to fully capture the extent to which using exclusive human milk diets actually reduce overall healthcare costs via improving the short and long term outcomes of extremely premature infants. Research to date only explores the financial impact for the first few years of life; therefore the true costs of these major morbidities are vastly underestimated and underreported. There are many unpublished trials and abstracts that are currently in process that will only strengthen the shift toward exclusive human milk-based diets, ideally making this common practice among Canadian centres in the very near future.
1 American Academy of Pediatrics. Section on Breastfeeding. Breastfeeding and the use of human milk. Pediatrics 2005; 115:496-506
2 American Academy of Pediatrics. Section on Breastfeeding. Breastfeeding and the use of human milk. Pediatrics 2012; 129:3;e827-41
3 Schanler RJ, Shulman RJ, Lau C. Feeding strategies for premature infants: Beneficial outcomes of feeding fortified human milk vs preterm formula. Pediatrics 1999;103:1150-7
4 Boyd CA, Quigley MA, Brocklehurst P, Donor Breast milk versus infant formula for preterm infants: a systematic review and meta-analysis. Arch Dis Child Fetal Neonatal Ed 2007;92:F169-75
5 Agostini C et al. Enteral nutrition supply for preterm infants: commentary from the European society for pediatric gastroenterology, hepatology, and nutrition committee on nutrition. JPGN 2010;50:1:85-91
6 Prolacta Bioscience, Industry, California: product description. http://www.prolacta.com/human-milk-fortifier
7 Sillivan S, et al. An Exclusively Human Milk-Based Diet is Associated with a Lower Rate of necrotizing Enterocolitis than a Diet of Human Milk and Bovine Milk-Based Products. J Pediatr 2010:156;562-7
8 Bell EF. Preventing necrotizing enterocolitis: what works and how safe? Pediatrics 2005:115;173-4
9 Abrams SA, Schanler RJ, Lee ML, Rechtman DJ. Greater Mortality and Morbidity in Extremely Preterm Infants fed a diet containing cow milk protein products. Breastfeed Med. 2014:9;1-8
10 Patel AL, Johnson TJ, Engstrom JL, Fogg LF, Jegier BJ et al. Impact of early human milk on sepsis and health-care costs in very low birth weight infants. J Perinatology 2013:33:514-19
11 Ganapathy V, Hay JW, Kim JH. Cost of necrotizing enterocolitis and cost-effectiveness of exclusively human milk-based products in feeding extremely premature infants. Breastfeed Med. 2012:7;29-37
12 Cristofalo EA, Schanler RJ, Blanco CL, Sullivan S, Trawoeger R, et al. Randomized trial of exclusive human milk versus preterm formula diets in extremely premature infants. J Pediatr. 2013;1-4
13 Ghandehari H, Lee ML, Rechtman DJ. An exclusive human milk based diet in extremely premature infants reduces the probability of remaining on total parenteral nutrition: a reanalysis of the data. BMC. 2012:5;188
14 Hair AB, Hawthorne KM, Chetta KE, Abrams, SA. Human milk feeding supports adequate growth in infants ≤1250 grams birth weight. BMC. 2013:6;459
15 Ehrankranz RA, Dusiuk AM, Vohr BR, Wright LL, Wrage LA, et al. Growth in the neonatal intensive care unit influences neurodevelopmental and growth outcomes of extremely low birth weight infants. Pediatrics. 2006.117:4; 1253-61