3 Reasons Why NICUs Are Passionate About Human Milk

Evi Dewhurst / February 2015


Human milk is the ideal source of nutrition for preterm infants, with a wealth of benefits to contribute to overall health and outcomes, and earning the descriptor “liquid gold.” February is a month celebrating love, and what’s not to love about the positive impacts of human milk in the NICU?

While it’s hard to pick only three reasons out of the many, here are three reasons human milk generates such passion in neonatal intensive care, all three of which promote better outcomes for this at-risk patient population:

It reduces intestinal permeability

One of the many reasons strict neonatal intensive care measures are necessary for the preterm infant is the higher risk of environmental pathogens. An example of these risks is the immature gastrointestinal system. The problem with an immature GI system is related to the nascent and susceptible junctions between cells of intestinal mucosa. These junctions close over time with maturity of the gastrointestinal system, but while they are immature they are at risk.

Taylor et al tested the impact of human milk on these junctions by measuring the lactulose to mannitol ratio (L/M ratio) in subjects’ urine. Why? The lactose molecule will only pass through intestinal walls if the junctions between cells of intestinal mucosa are open. If the junctions have matured and closed (meaning now have reduced exposure to environmental pathogens) then the L/M ratio would be reduced.

They found that infants receiving human milk showed positively impacted L/M ratios: they were significantly lower. In addition, infants who received greater than 75% human milk feeds demonstrated a 3.8-fold lower composite median L/M ratio (and decreased intestinal permeability). This leads to the conclusion that human milk allows the junctions to mature and thus prevent environmental pathogen access.

The authors stated, “Preterm infant intestinal permeability was significantly decreased for those receiving human milk versus formula in a dose-related manner in the first postnatal month.”

It lowers the risk of NEC

Necrosis of the bowel tissue is something no clinician ever wants to see. Necrotizing enterocolitis is a disorder known for its devastating impact on a preterm infant, leading to serious and life-threatening complications. Out of the unfortunate infants who develop NEC, about 40% of them will not survive. These complications also impact a hospital on a financial scale, with estimates of medical NEC costing a hospital $74,004 and surgical NEC costing $198,040.2 The good news is that human milk has a positive effect on the health of preterm infants’ intestines.

Meinzen-Derr et al discovered that increasing amounts of human milk for extremely low birth weight infants in the first two weeks was related to survival time in which the infant was free from NEC. Johns Hopkins found in their studies that if mothers were not producing enough milk on their own, supplementing with donor milk for the feeds seemed to offer the same NEC-preventing benefits. Combining with formula did not.

“An earlier study by the same team showed that babies who get their own mother’s milk fortified with the standard cow milk protein are more prone to NEC than babies given a combination of their mothers’ milk fortified with human donor milk.”

They noted that the infants who received the human milk also tolerated feeds better. This in turn eliminated the continued need for supplemental IV nutrition (after an average of 27 days). The overall impact of human milk on the gut seems impressive in its scope and continued studies reinforce its value.

It cuts the risk of sepsis

Imagine decreasing the odds of sepsis by 20% in a very low birth weight infant. It’s not hypothetical; it’s science. The science of human milk. Rush University Medical Center researchers discovered that every 10 milliliters of human milk per kilogram a VLBW infant received in the first 28 days of life actually did just that. That was great news for patient outcomes.

As an added bonus, the financial investment to accomplish it was merited. Dr. Aloka L. Patel, who led the Rush University research, said of their findings, “The substantial NICU hospital cost savings associated with increased dosages of human milk are likely to offset the maternal and institutional costs of providing and feeding human milk, such as breast pump rental, lactation care providers and milk storage.”

“A daily dose of 25 to 49.99 milliliters of human milk per kilogram cut NICU costs by more than $20,000, while 50 milliliters per kilogram per day lowered NICU costs by nearly $32,000.”

Late-onset sepsis is also a common occurrence in VLBW infants, at about a 22% incidence rate. Its impact is severe, leading to potential neurological disabilities, longer lengths of stay and of course, higher costs. If human milk could minimize that number it would have even more far reaching impacts for patient outcomes in the NICU and its financial impact to healthcare. Continuing research shows promising benefits related to minimizing sepsis risk based on an exclusive human milk diet.

These are just three ways at-risk infants in the NICU benefit from human milk. The actual list of benefits stretches even further, but there is not enough room here to address them all! Studies have generally revealed that a diet of human milk for at-risk infants leads to decreased length of stay, improved patient outcomes and reduced expense. No wonder human milk incites such devotion from healthcare practitioners. It seems human milk is literally one of the best special-delivery valentines of all for these infants. And that’s something we can all love.


1 Taylor SN, Basile LA, Ebeling M, Wagner CL. Intestinal permeability in preterm infants by feeding type: mother’s milk versus formula. Breastfeeding Medicine, 2009; 4(1): 11-5.

2 Ganapathy V1, Hay JW, Kim JH. Costs of necrotizing enterocolitis and cost-effectiveness of exclusively human milk-based products in feeding extremely premature infants. Breastfeed Med. 2012 Feb;7(1):29-37. doi: 10.1089/bfm.2011.0002. Epub 2011 Jun 30.

3 Meinzen-Derr J, Poindexter B, Wrage L, Morrow AL, Donovan EF. Role of human milk in extremely low birth weight infants’ risk of necrotizing enterocoloitis or death. Journal of Perinatology, 2009; 29(1): 57-62.

4. Formula-Fed Preemies at Higher Risk for Dangerous GI Condition, Than Babies Who Get Donor Milk. hopkinsmedicine.org/news/media/releases/formula_fed_preemies_at_higher_risk_for_dangerous_gi_condition_surgery_than_babies_who_get_donor_milk

5 Maureen W Groer, Angel A Luciano, Larry J Dishaw, Terri L Ashmeade2, Elizabeth Miller and Jack A Gilbert. Development of the preterm infant gut microbiome: a research priority. Microbiome 2014, 2:38  doi:10.1186/2049-2618-2-38

6 A L Patel, T J Johnson, J L Engstrom, L F Fogg, B J Jegier, H R Bigger, P P Meier. Impact of early human milk on sepsis and health-care costs in very low birth weight infants. Journal of Perinatology, 2013; DOI: 10.1038/jp.2013.2

7 Breast milk reduces risk of sepsis and intensive care costs in very-low-birth-weight infants. http://www.sciencedaily.com/releases/2013/02/130206162129.htm