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As a newborn hospitalist, I am frequently called upon to discuss the benefits of breastfeeding and breast milk with families. There is good evidence to support encouraging breastfeeding in a reasonable manner that emphasizes maternal choice, and providing assistance that increases the likelihood of success. There is equally compelling evidence that aggressive “support” can be harmful to newborns, and can result in sometimes significant maternal psychosocial distress. There are many ways to approach feeding of the newborn that will result in a healthy child and a happy mother. Breast is not always best.

I’m not going to get into the specific details regarding the benefits of breastfeeding compared to formula in this post. It’s a complex topic and unfortunately the literature is full of biased studies seemingly designed to show that breastfeeding is superior by not taking into account important socioeconomic factors. Historically there has been much “white hat bias” in breastfeeding research, with proponents having already decided that it is the morally right thing for mothers to do. This bias influences the way that many proponents interpret the available data, design research protocols, and implement campaigns meant to increase rates.

In my opinion, much of the benefit of breastfeeding comes from the environment surrounding a child who is breastfed rather than the actual chemicals in the milk. There are almost certainly some components specific to human breast milk that are beneficial to babies and are not found in modern formula, but differences in outcomes are mostly appreciated only in large populations rather than individual newborns. Many, many babies need to be breastfed to prevent one case of gastrointestinal infection or asthma, for example. This means that most breastfed babies will not have any appreciable advantage over most formula fed babies if their environment is taken into account.

There is one population of newborns that I do think of as unique when it comes to benefits from breastfeeding and breast milk. Premature infants, particularly those born close to the current limits of viability, appear to reap far greater rewards than the typical near-term or term infant. One of the best examples of this is the significant reduction in the occurrence of necrotizing enterocolitis (NEC) in babies who receive donor or maternal expressed breast milk compared to those who are fed formula. NEC is a terrible condition that can result in severe illness, perforation and subsequent loss of bowel, and death.

Another clear benefit of breast milk in premature infants is improved neurocognitive outcomes. It isn’t as obvious as the reduced risk of NEC, and it isn’t the only important factor, but it’s real. The authors of a recently published study in the European Journal of Pediatrics are attempting to add another potentially huge benefit to this list.

Intranasal breast milk for premature infants with severe intraventricular hemorrhage – an observation

Along with NEC, the diagnosis of intraventricular hemorrhages (IVH) is a common and frustrating occurrence in neonatal intensive care units. The earlier and smaller that a baby is born, the more likely they are to suffer bleeding into the hollow cavities inside the brain, which are called the ventricles. These bleeds typically occur in the first few days after birth and, depending on the severity, can result in severe damage to the brain and lifelong neurological sequelae such as cerebral palsy.

The authors of the new study investigated the application of breast milk into the nasal passages of premature infants who have suffered a severe IVH as a possible treatment. My initial reaction was not exactly positive because miraculous uses for breast milk are not new and they are virtually always implausible and based on personal anecdotes. Still, this was published in a respectable journal and a safe and effective (not to mention cheap) therapy that improves neurocognitive outcomes in these babies would be a really big deal. There is currently no treatment for IVH, only the treatment of other conditions that might worsen overall outcomes or the surgical placement of drains to reduce excess pressure inside the brain.

Is it plausible?

Yes…kind of. According to the paper, the reason that this study even took place was because one of the neonatologists decided to just give it a try in a premature infant who had suffered a severe IVH. They dropped a little of mother’s milk into each nostril three times a day for several weeks and the child had an “intriguing good course”, which served as impetus for treating 15 additional babies over the next two years.

But why would the neonatologist decide to give this treatment a try? As described by the authors of the study, there is murine data showing that certain molecules can bypass the blood-brain-barrier after intranasal administration. Furthermore, breast milk is known to contain chemicals associated with growth, development, and survival of neurons. There are also stem cells in breast milk with multipotent and perhaps even pluripotent capabilities.

So they thought that perhaps these brain friendly chemicals in breast milk might access the brain via the nasal passage and improve recovery. The plausibility of this is definitely not homeopathy level, not even close, but it’s a stretch in my opinion. And while there is evidence of better general neurocognitive outcomes in premature infants receiving breast milk, there is no evidence that these babies have faster resolution of IVH or better outcomes specific to that diagnosis such as less severe brain injury or need for surgery.

And virtually all young infants, particularly those with immature feeding mechanisms, have intranasal penetration of feeds. Even when fed with a tube that bypasses the oral cavity, reflux of feeds into the nasal passages is almost equally universal. So it is hard to imagine that intentional intranasal application of breast milk is somehow different and would have unique benefits in the setting of severe IVH.

Were the results interpreted fairly?

As mentioned above, the study involved the initial baby with her “intriguing good course” and then 15 subsequent anecdotes over the following 2 years (2012-2014) where the mother’s breast milk was administered by drops into the nose for several weeks after diagnosis of severe IVH. They then looked back over the previous 4 years (2010-2014) to find 15 babies with severe IVH who were also breastfed but who did not undergo intranasal application. So this was a very small, retrospective case-control study, meaning that confounding variables might play a role in any outcome differences.

All of the babies received the standard of care for their institution, so they all had serial brain ultrasounds which were read by pediatric radiologists blinded to whether or not a baby had been receiving the intranasal breast milk. The tracked initial IVH grading and worst severity at any point, degree of ventricular dilatation, white matter damage (degree of cystic defect) at discharge and worst severity at any point, death within 2 weeks of birth, survival to discharge, and need for surgical intervention.

Despite choosing not to adjust for the multiple comparisons, citing the study’s “exploratory character” as the reason, no outcomes differences were found to be statistically significant. But despite the small number of subjects, and the lack significance, they concluded that they had discovered a “trend for less severe cystic defects” and called for “further controlled investigation”. This, in my opinion, is not an appropriate interpretation of these results. A more honest conclusion might have been that this data did not show benefit from intranasal breast milk, but we still think it’s a pretty neat idea and want to see how this pans out. I also think it’s important to point out that even if this trend ends up being real, these structural changes wouldn’t necessarily equate to improved long-term neurocognitive outcomes.

Is there any risk?

Use of freshly pumped milk from the child’s mother for intranasal application would not be risk free, but it’s far from dangerous. I mean, we do feed this milk to the babies. The volume is very low such that aspiration into the lungs would not really be a problem. There are infections agents that are sometimes found in breast milk, but again this would be unlikely to be much of a concern unless someone were to use a less safe supply of breast milk. One potential risk would be the creep that occurs when unproven ideas reach a wider audience. I can imagine people extrapolating to older babies and different conditions. Ultimately, I don’t really see this as a risky intervention. I just don’t think it is going to work.

Conclusion: Let’s withhold judgement on intranasal breast milk

This study doesn’t really tell us whether or not intranasal breast milk will be beneficial to premature infants with intraventricular hemorrhages. But I don’t think it’s particularly plausible. That being said, it isn’t really risky and it is cheap as far as interventions in this population go. I’m not opposed to further studies, but I won’t exactly be holding my breath.

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Posted by Clay Jones

Clay Jones, M.D. is a pediatrician and a regular contributor to the Science-Based Medicine blog. He primarily cares for healthy newborns and hospitalized children, and devotes his full time to educating pediatric residents and medical students. Dr. Jones first became aware of and interested in the incursion of pseudoscience into his chosen profession while completing his pediatric residency at Vanderbilt Children’s Hospital a decade ago. He has since focused his efforts on teaching the application of critical thinking and scientific skepticism to the practice of pediatric medicine. Dr. Jones has no conflicts of interest to disclose and no ties to the pharmaceutical industry. He can be found on Twitter as @SBMPediatrics and is the co-host of The Prism Podcast with fellow SBM contributor Grant Ritchey. The comments expressed by Dr. Jones are his own and do not represent the views or opinions of Newton-Wellesley Hospital or its administration.