Human Milk Cuts Premature Infant NEC Risk by 38%

Breastfeeding and Infant Health: A 38% Lower Risk for a Deadly Intestinal Disease

For infants born before 28 weeks of gestation in an Australian neonatal intensive care unit, reliable access to pasteurised donor human milk (PDHM) lowered the risk of necrotising enterocolitis (NEC) by 38%. That finding, from a 2026 cohort study published in the Journal of Paediatrics and Child Health, provides strong population-level evidence for a life-saving intervention. NEC is a devastating intestinal disease that primarily affects preterm infants, and human milk is a powerful protective factor. This article examines the specific health and developmental outcomes linked to breastfeeding and donor milk, separating established evidence from assumptions and providing clear guidance for parents and caregivers.

What is Necrotising Enterocolitis and Why is Human Milk Protective?

Necrotising enterocolitis is a serious gastrointestinal condition where intestinal tissue becomes inflamed and dies. It is a leading cause of mortality and morbidity in preterm infants, particularly those with very low birth weights. The exact cause is not fully understood but is believed to involve an immature intestinal barrier, an abnormal gut microbiome, and an exaggerated inflammatory response. Human milk contains bioactive components—including immunoglobulins, growth factors, prebiotic oligosaccharides, and beneficial bacteria—that help mature the gut, modulate the immune system, and outcompete harmful pathogens. Formula lacks these dynamic, species-specific protective factors, which explains the higher risk of NEC associated with its use in vulnerable preterm populations.

The Science of Breast Milk: More Than Nutrition

Human milk is a complex, live substance that adapts to an infant’s needs. It is not merely food but a sophisticated biological system supporting development.

Immunological Programming and Gut Health

Colostrum, the first milk, is especially rich in secretory IgA, an antibody that coats the infant’s gut lining, providing a passive immune defense. Milk oligosaccharides are indigestible sugars that act as prebiotics, selectively feeding beneficial gut bacteria like Bifidobacterium. This helps establish a healthy microbiome, which is fundamental to immune regulation and metabolic health. The study from the Australian and New Zealand Neonatal Network did not find a change in overall infection rates with PDHM access, but its primary focus was on NEC, a condition intimately linked to gut microbiome dysbiosis.

Neurodevelopmental and Long-Term Benefits

Beyond acute protection, breast milk is linked to long-term advantages. Some studies associate breastfeeding with modest gains in cognitive scores, potentially linked to the presence of long-chain polyunsaturated fatty acids like DHA. For more on the role of specific nutrients in early brain development, see our article on DHA for Brain Development: The First 1000 Days. It is important to note that disentangling the direct effect of milk from socioeconomic and parenting factors is challenging, and observed benefits are often multifactorial.

National Milk Banking: The Australian Lifeblood Cohort Study

The 2026 study, led by Klein LD and colleagues across 15 Australian NICUs, offers a real-world test of donor milk’s impact. Before 2018, most Australian NICUs lacked a guaranteed supply of pasteurised donor human milk. The establishment of a national PDHM service through Lifeblood, the national blood service, created a natural experiment.

Study Design and Key Findings

Researchers analyzed data from 4,395 infants born before 32 weeks’ gestation from 2018 to 2020. They compared outcomes during periods when a NICU had an assured PDHM supply versus when it did not. After adjusting for confounders like gestational age and birth weight, the results were clear: for infants born before 28 weeks, the adjusted relative risk of NEC was 0.62 (95% CI 0.46-0.83) when PDHM was available—a 38% risk reduction. “Reliable access to PDHM was associated with reduced risk of NEC for infants born < 28 weeks' gestation in Australian NICUs," the authors concluded.

Other Outcomes and an Unexpected Finding

The study found no significant association between PDHM access and rates of death, infection, retinopathy of prematurity, or breast milk feeding at discharge. One unexpected result was a lower weight at discharge (2828.8g vs. 2939.56g) when PDHM was available. The clinical significance of this 111-gram difference is unclear and may relate to changes in feeding protocols or the nutritional composition of donor milk, which can vary. This finding underscores that donor milk, while protective against NEC, must be managed as part of a comprehensive nutritional strategy to ensure optimal growth.

Practical Applications: From NICU to Home

For Parents of Preterm Infants

If your infant is in the NICU, discuss feeding options with the clinical team. Mother’s own milk is the first choice. If a mother’s milk is insufficient or unavailable, pasteurised donor human milk is the recommended alternative to formula for preterm infants, specifically to reduce NEC risk. The Australian study supports this standard of care. Parents should know that donor milk is rigorously screened and pasteurised for safety, a process that eliminates pathogens while retaining most beneficial components.

Building and Sustaining a Milk Supply

For mothers of preterm infants, initiating and maintaining milk production can be challenging. Frequent, effective milk expression starting within the first few hours after birth is vital. Hospital lactation support and the use of clinical-grade breast pumps are essential. Our Breastfeeding Support, Infant Health & Development Guide offers evidence-based strategies. Persistence is key; even small volumes of mother’s own milk provide significant benefit.

The Role of Donor Milk Banks

Donor milk banks, like the Lifeblood service in Australia, are critical public health infrastructure. Healthy lactating individuals with an oversupply can donate milk after a screening process similar to blood donation. This milk is pooled, pasteurised, and distributed primarily to NICUs. Expanding access to donor milk remains a priority for global infant health.

Frequently Asked Questions

Does donor milk provide the same benefits as a mother’s own milk?

Pasteurised donor human milk retains many protective benefits and is superior to formula for NEC prevention, but the pasteurisation process does reduce some bioactive components. A mother’s own milk, tailored specifically to her infant, remains the ideal source.

If I can’t produce enough milk, is my baby at a major disadvantage?

No. While every drop of a mother’s own milk helps, modern neonatal care uses donor milk and specialised fortifiers to support infant health. The goal is to provide as much human milk as possible, but the NICU team will ensure your baby’s nutritional needs are met safely.

Does breastfeeding prevent allergies like egg or peanut allergies?

Breastfeeding provides general immune support, but specific allergy prevention is more strongly linked to the early introduction of allergenic foods when an infant is ready for solids. For details, see our article on Early Peanut & Egg Feeding Prevents Child Allergies.

Key Takeaways

• For preterm infants born before 28 weeks, access to pasteurised donor human milk (PDHM) is associated with a 38% lower risk of necrotising enterocolitis (NEC), a serious intestinal disease.
• Human milk acts as a biological system, providing immune protection, promoting a healthy gut microbiome, and supporting development beyond basic nutrition.
• Mother’s own milk is the first choice for infant feeding; pasteurised donor human milk is the recommended alternative when a mother’s milk is not available, especially in the NICU.
• The 2026 Australian cohort study found PDHM access did not significantly change overall infection rates or mortality, and was linked to a slightly lower discharge weight, highlighting that nutritional management is complex.
• National donor milk banks, like Australia’s Lifeblood service, are vital public health resources that standardise access to this life-saving intervention for the most vulnerable infants.
• Parents of preterm infants should work closely with NICU staff to establish a mother’s milk supply and understand the role of donor milk in their infant’s care plan.
• While breastfeeding offers significant health benefits, multiple factors influence child development, and successful feeding can take many forms with professional support.

Sources:
https://pubmed.ncbi.nlm.nih.gov/423