Can a Cow's "First Milk" Help Premature Babies Feed Better? A New Trial Says: Safe, but No Extra Benefit

What the FortiColos CN study found when it added bovine colostrum to human milk for very premature babies

A new study of 146 very premature babies in China tested whether adding bovine colostrum — the rich "first milk" a cow makes just after giving birth — to their mothers' milk would help them digest feeds more easily than a standard cow's-milk supplement. The answer was no: babies given colostrum had the same rate of feeding problems, the same growth, and the same complication rates as babies given the usual supplement. The good news is that colostrum was completely safe and well tolerated. It simply did not provide the extra benefit that scientists had hoped for, at least when used this way.

Why This Question Matters

Babies born very early — before 32 weeks of pregnancy — are among the most fragile patients in any hospital. Breast milk is the best food for them, but on its own it does not contain enough protein and minerals for a baby who should still be growing rapidly inside the womb. So for decades, neonatal teams have "fortified" breast milk by stirring in a nutrient powder, a practice recommended by international expert groups [1][2]. Almost all of these fortifier powders are made from ordinary cow's milk. They work, but researchers have long wondered whether a richer, more natural ingredient might do even better — helping the baby's delicate, immature gut mature and defend itself.

Bovine colostrum is a natural candidate. In the first day or two after a cow gives birth, its milk is packed with protein, antibodies, and protective substances that ordinary cow's-milk powders lose during processing [3]. In studies using newborn piglets — whose guts closely resemble those of premature human babies — colostrum protected against serious intestinal injury far better than standard formula-based supplements [4]. And in some earlier baby studies where colostrum was given as one of the very first feeds, there were encouraging hints: fewer cases of a serious eye condition of prematurity [5], and signs of a healthier developing immune system [6]. Those promising clues are exactly why researchers kept testing it.

How Families Used to Face This Problem

For years, the choice of which supplement to add to breast milk has been made largely on availability and cost, because no ingredient had clearly proven better than another for the outcomes families care about most — comfortable feeding, steady growth, and avoiding complications. An earlier pilot study found colostrum was well tolerated but could not prove it helped [7]. A larger Danish trial, called FortiColos, then compared colostrum against a standard supplement in babies whose feeds were increased quickly, and again found the differences were small or absent [8]. Researchers wondered whether the picture might change in hospitals where feeds are increased more slowly — a common approach in many parts of the world — because a protein-rich, protective ingredient might matter more when a baby is fed cautiously over a longer period. This new trial was designed to test exactly that idea.

What the Researchers Did

The study, called FortiColos CN [1], was run at two hospitals in Shenzhen, China, between 2019 and 2021. Babies born between 26 and 31 weeks of pregnancy who needed fortification were randomly assigned — like a coin toss — to have their breast milk (from their own mother, or from a donor when needed) enriched with either bovine colostrum or a standard cow's-milk supplement. Neither ingredient was started until the baby was already tolerating a reasonable amount of milk, and it was continued for at least two weeks. In total, 146 babies were included in the main analysis, 74 receiving colostrum and 72 receiving the standard supplement. The main thing the researchers measured was "feeding intolerance" — any time the team had to pause or hold back feeds because the baby's digestion was struggling.

What They Found

The two groups came out remarkably even. Feeding problems happened in about 32 out of every 100 colostrum babies and 29 out of every 100 standard-supplement babies — a difference small enough to be due to chance [1]. That result held whether the babies were born earlier or slightly later within the study's age range, and it held when the researchers looked only at the larger of the two hospitals. The babies reached full feeds at the same pace (around three weeks), went home at about the same time — a median of roughly 54 days — and had the same length of hospital stay. Growth in weight and head size was the same, though there was a faint hint that colostrum babies grew slightly better in length, and regained their birth weight a little faster. The researchers were careful not to overstate these small signals, since none reached the level of certainty scientists require before calling a difference real.

The complications that most frighten parents of premature babies were also equally uncommon in both groups: the serious intestinal illness necrotising enterocolitis (4 versus 3 babies), bloodstream infections (32 versus 36), the lung condition bronchopulmonary dysplasia (25 versus 25), the eye condition retinopathy of prematurity (9 versus 10), and bleeding in the brain (4 versus 5) [1]. An independent safety committee reviewed every death and concluded none were caused by the study feeds. Blood tests did show a few small differences — colostrum babies had slightly higher levels of certain building-block nutrients (amino acids) and minerals, and slightly lower sodium — which tells doctors that a hospital switching to colostrum would need to keep an eye on mineral levels rather than assume the two products are identical.

It helps to understand why a promising ingredient can come up empty in a careful test like this. A baby being fed breast milk gets most of its protein and nourishment from the milk itself; the fortifier powder stirred in adds only about a fifth of the total. So even if colostrum is a richer, more protective ingredient than a standard powder, it is a richer version of a relatively small slice of the baby's diet — and that limits how much difference it can make to how the baby digests and grows. The researchers also point out that both hospitals in this study increased feeds cautiously and slowly, which meant more than 8 in 10 babies were still on fortifier when they went home. In other words, there was a lot of "diet" left for the fortifier to potentially influence, and it still made no measurable difference — which makes the finding all the more convincing. This is not a study that failed to find an answer; it is a study that found a clear one.

What This Means for Families

Feeding is one of the most anxious parts of a premature baby's hospital stay for many families, and it is natural to wonder whether a more "natural" or premium ingredient would give your baby an edge. If your baby is in the NICU, the practical message is reassuring on two fronts. First, bovine colostrum is a safe ingredient — it did not cause harm and was well tolerated, consistent with the standard supplements that have been compared against it many times before [9][10]. Second, you do not need to worry that your baby is missing out if their unit uses a conventional fortifier: in this careful test, colostrum offered no extra advantage for feeding, growth, or avoiding complications. The near-universal slow early weight gain seen in both groups — measured against the widely used Fenton growth chart for premature babies [11] — is a reminder that helping tiny babies grow well is a challenge no single ingredient solves on its own [12].

What Researchers Are Working On Next

This trial does not close the book on bovine colostrum — it redirects it. The colostrum's most convincing benefits in earlier studies came when it was used as one of the very first feeds, priming the newborn gut, rather than as a later add-in to milk. Scientists now want to test it in that role, in larger trials that combine results across many hospitals so that rare complications can be measured reliably, and to adjust the colostrum recipe to correct the small mineral gaps this study uncovered. They are also interested in whether babies with particular needs — such as those who were unusually small at birth — might benefit more than the general group did; in this study, too few babies were very small for the researchers to answer that question. Another open question is whether adjusting the colostrum recipe, or the way it is processed and pasteurised, might preserve more of the natural protective ingredients that gentle handling is meant to protect. These are the kinds of refinements that turn a promising idea into a proven treatment, and they take time and large numbers of babies to test properly. For now, families can take comfort in a simple, honest conclusion: bovine colostrum is a safe choice, but not a magic one, and the standard supplements their baby may be receiving are doing the job just as well [1].

References

  1. Jiang P-P, Huang H-Y, Zhao L, et al. Bovine colostrum as a human milk fortifier for very preterm infants with slow feeding advancement: a randomized controlled trial. Pediatric Research. 2026. doi:10.1038/s41390-026-04768-0 ↩
  2. Arslanoglu S, Boquien C-Y, King C, et al. Fortification of human milk for preterm infants: update and recommendations of the EMBA Working Group on Human Milk Fortification. Frontiers in Pediatrics. 2019;7:76. doi:10.3389/fped.2019.00076 ↩
  3. Sangild PT, Vonderohe C, Melendez Hebib V, Burrin DG. Potential benefits of bovine colostrum in pediatric nutrition and health. Nutrients. 2021;13:2551. doi:10.3390/nu13082551 ↩
  4. Sun J, Li Y, Nguyen DN, et al. Human milk fortification with bovine colostrum is superior to formula-based fortifiers to prevent gut dysfunction, necrotizing enterocolitis, and systemic infection in preterm pigs. JPEN Journal of Parenteral and Enteral Nutrition. 2019;43:252–262. doi:10.1002/jpen.1422 ↩
  5. Farag MM, Gouda MH, Almenawy MA, et al. Do preterm infants' retinas like bovine colostrum? A randomized controlled trial. Italian Journal of Pediatrics. 2024;50:218. doi:10.1186/s13052-024-01781-z ↩
  6. Ismail RIH, Awad HA, Imam SS, et al. Gut priming with bovine colostrum and T regulatory cells in preterm neonates: a randomized controlled trial. Pediatric Research. 2021;90:650–656. doi:10.1038/s41390-020-01344-y ↩
  7. Juhl SM, Ye X, Zhou P, et al. Bovine colostrum for preterm infants in the first days of life: a randomized controlled pilot trial. Journal of Pediatric Gastroenterology and Nutrition. 2018;66:471–478. doi:10.1097/MPG.0000000000001774 ↩
  8. Ahnfeldt AM, Aunsholt L, Hansen BM, et al. Bovine colostrum as a fortifier to human milk in very preterm infants — a randomized controlled trial (FortiColos). Clinical Nutrition. 2023;42:773–783. doi:10.1016/j.clnu.2023.03.008 ↩
  9. Chinnappan A, Sharma A, Agarwal R, et al. Fortification of breast milk with preterm formula powder vs human milk fortifier in preterm neonates: a randomized noninferiority trial. JAMA Pediatrics. 2021;175:790–796. doi:10.1001/jamapediatrics.2021.0678 ↩
  10. Premkumar MH, Pammi M, Suresh G. Human milk-derived fortifier versus bovine milk-derived fortifier for prevention of mortality and morbidity in preterm neonates. Cochrane Database of Systematic Reviews. 2019;11:CD013145. doi:10.1002/14651858.CD013145 ↩
  11. Fenton TR, Kim JH. A systematic review and meta-analysis to revise the Fenton growth chart for preterm infants. BMC Pediatrics. 2013;13:59. doi:10.1186/1471-2431-13-59 ↩
  12. Brown JVE, Embleton ND, Harding JE, McGuire W. Multi-nutrient fortification of human milk for preterm infants. Cochrane Database of Systematic Reviews. 2020;6:CD000343. doi:10.1002/14651858.CD000343.pub4 ↩