Exclusive human milk (EHM) diets using either mother’s own milk or donor milk plus a human based human milk fortifier have been the subject of many papers over the last few years. Such papers have demonstrated reductions is such outcomes as NEC, length of stay, days of TPN and number of times feedings are held due to feeding intolerance to name just a few outcomes. There is little argument that a diet for a human child composed of human milk makes a great deal of sense. Although we have come to rely on bovine sources of both milk and fortifier when human milk is unavailable I am often reminded that bovine or cow’s milk is for baby cows.
Challenges with using an exclusive human milk diet.
While it makes intuitive sense to strive for an exclusive human milk diet, there are barriers to the same. Low rates of maternal breastfeeding coupled with limited or no exposure to donor breast milk programs are a clear impediment. Even if you have those first two issues minimized through excellent rates of breast milk provision, there remains the issue of whether one has access to a human based fortifier to achieve the “exclusive” human milk diet.
The “exclusive” approach is one that in the perfect world we would all strive for but in times of fiscal constraint there is no question that any and all programs will be questioned from a cost-benefit standpoint. The issue of cost has been addressed previously by Ganapathy et al in their paper Costs of Necrotizing Enterocolitis and Cost-Effectiveness of Exclusively Human Milk-Based Products in Feeding Extremely Premature Infants. The authors were able to demonstrate that choosing an exclusive human milk diet is cost effective in addition to the benefits observed clinically from such a diet. In Canada where direct costs are more difficult to visualize and a reduction in nursing staff per shift brings about the most direct savings, such an argument becomes more difficult to achieve.
Detractors from the EHM diet argue that we have been using bovine fortification from many years and the vast majority of infants regardless of gestational age have little challenge with it. Growth rates of 15-20 g/kg/d are achievable using such fortification so why would you need to treat all patients with an EHM diet?
A Rescue Approach
In our own centre we were faced with these exact questions and developed a rescue approach. The rescue was designed to identify those infants who seemed to have a clear intolerance to bovine fortifier as all of the patients we care for under 1250g receive either mother’s own or donor milk. The approach used was as follows:
A. < 27 weeks 0 days or < 1250 g
i. 2 episode of intolerance to HMF
ii. Continue for 2 weeks
This month we published our results from using this targeted rescue approach in Winnipeg, Human Based Human Milk Fortifier as Rescue Therapy in Very Low Birth Weight Infants Demonstrating Intolerance to Bovine Based Human Milk Fortifier with Dr. Sandhu being the primary author (who wrote this as a medical student with myself and others. We are thrilled to share our experience and describe the cases we have experienced in detail in the paper. Suffice to say though that we have identified value in such an approach and have now modified our current approach based on this experience to the following protocol for using human derived human milk fortifier in our centre to the current:
A. < 27 weeks 0 days or < 1250 g
i. 1 episode of intolerance to HMF
ii. Continue for 4 weeks
B. ≥ 27 week 0 days or ≥ 750g
i. 2 episodes of intolerance to HMF
ii. Continue for 4 weeks or to 32 weeks 0 days whichever comes sooner
We believe given our current contraints, this approach will reduce the risk of NEC, feeding intolerance and ultimately length of stay while being fiscally prudent in these challenging times. Given the interest at least in Canada with what we have been doing here in Winnipeg and with the publication of our results it seemed like the right time to share this with you. Whether this approach or one that is based on providing human based human milk fortifier to all infants <1250g is a matter of choice for each institution that chooses to use a product such as Prolacta. In no way is this meant to be a promotional piece but rather to provide an option for those centres that would like to use such products to offer an EHM diet but for a variety of reasons have opted not to provide it to all.
Breast milk has many benefits and seems to be in the health care news feeds almost daily. As the evidence mounts for long term effects of the infant microbiome, more and more centres are insisting on providing human milk to their smallest infants. Such provision significantly reduces the incidence of NEC, mortality and length of stay. There is a trade-off though in that donor milk after processing loses some of it’s benefits in terms of nutritional density. One such study demonstrated nutritional insufficiencies with 79% having a fat content < 4 g/dL, 56% having protein content< 1.5 g/dL, and 67% having an energy density < 67 kcal/dL (< 20 Kcal/oz). It is for this reason that at least in our unit many infants on donor milk ultimately receive a combination of high fluid volumes, added beneprotein or cow’s milk powders to achieve adequate caloric intake. Without such additions, growth failure ensues. Such growth failure is not without consequence and will be the topic of a future post. One significant concern however is that failure of our VLBW infants to grow will no doubt impact the timing of discharge as at least in our unit, babies less than 1700g are unlikely to be discharged. With the seemingly endless stream of babies banging on the doors of the NICU to occupy a bed, any practice that leads to increasing lengths of stay will no doubt slow discharge and cause a swelling daily patient census.
What if increasing volume was not an option?
Such might be the case with a baby diagnosed with BPD. Medical teams are often reluctant to increase volumes in these patients due to concerns of water retention increasing respiratory support and severity of the condition. While diuretics have not been shown to be of long term benefit to BPD they continue to be used at times perhaps due to old habits or anecdotal experiences by team members of a baby who seemed to benefit. Such use though is not without it’s complications as the need to monitor electrolytes means more needle sticks for these infants subjecting them to painful procedures that they truly don’t need. Alternatively, another approach is to restrict fluids but this may lead to hunger or create little room to add enough nutrition again potentially compromising the long term health of such infants.
Amy Hair and colleagues recently published the following study which takes a different approach to the problem Premature Infants 750–1,250 g Birth Weight Supplemented with a Novel Human Milk-Derived Cream Are Discharged Sooner
This paper is essentially a study within a study. Infants taking part in an RCT of Prolacta cream (Prolacta being the subject of a previous post) were randomized as well to a cream supplement vs no cream. The cream had a caloric density of 2.5 Kcal/mL and was added to donor milk or mother’s own milk when the measured caloric density was less than 19 Kcal/oz. The study was small (75 patients; control 37, cream 38) which should be stated upfront and as it was a secondary analysis of the parent study was not powered to detect a difference in length of stay but that was what was reported here. The results for the groups overall were demonstrated an impact in length of stay and discharge with the results shown below.
|PDA ligation %
|PDA treated medically %
|Length of stay, days
|PMA at discharge, weeks
What about those with sensitivity to fluid?
Before we go into that let me state clearly that this group comparison is REALLY SMALL (control with BPD=12 vs cream with BPD=9). The results though are interesting.
||BPD control (N=12)
||BPD cream N=9
|Length of stay, days
|PMA at discharge, weeks
So they did not reach statistical significance yet one can’t help but wonder what would have happened if the study had been larger or better yet the study was a prospective RCT examining the use of cream as a main outcome. That of course is what no doubt will come with time. I can’t help but think though that the results have biologic plausibility. Providing better nutrition should lead to better growth, enhanced tissue repair and with it earlier readiness for discharge.
One interesting point here is that the method that was used to calculate the caloric density of milk was found to overestimate the density by an average of 1.2 Kcal/oz when the method was compared to a gold standard. Given that fortification with cream was only to be used if the caloric density of the milk fell below 19 Kcal/oz where average milk caloric density is 20 Kcal/oz there is the distinct possibility that the eligible infants for cream were underestimated. Could some of the BPD be attributable to infants being significantly undernourished in the control group as they actually were receiving <19 Kcal/oz but not fortified? Could the added fortification have led to faster recovery from BPD?
Interesting question’s in need of answers. I look forward to seeing where this goes. I suspect that donor milk is not enough, adding a little cream may be needed for some infants especially those who have trouble tolerating cow’s milk fortification.
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