Based on current medical research, there is some evidence that probiotics in general can help reduce the risk of necrotizing enterocolitis (NEC) in premature infants, but the specific evidence for Lactobacillus reuteri is more limited compared to other probiotic strains.

Here's a summary of what is known:

General Probiotic Evidence

Multiple meta-analyses and systematic reviews have shown that probiotic supplementation (using various strains) reduces the risk of severe NEC (Stage II or III) and all-cause mortality in preterm infants. This is one of the more robust findings in neonatal medicine.

Lactobacillus reuteri Specifically

• Lactobacillus reuteri (particularly the strain DSM 17938) has been studied in a number of clinical trials for NEC prevention.
• Some trials have reported that L. reuteri supplementation in very low birth weight infants is associated with a lower incidence of NEC.
• However, the body of evidence for L. reuteri as a single strain is smaller and less conclusive than for multi-strain probiotics or other single strains like Lactobacillus rhamnosus GG or Bifidobacterium species.
• A few studies and subgroup analyses suggest a potential benefit, but not all have reached statistical significance.

Key Considerations

• Strain specificity matters: The effects of one probiotic strain cannot be generalized to another. The limited data on L. reuteri does not necessarily mean it is ineffective — it primarily means the evidence base is not as strong.
• Combination probiotics (e.g., products containing both Lactobacillus and Bifidobacterium strains) tend to show the strongest and most consistent reductions in NEC rates.
• Safety: L. reuteri is generally considered safe in preterm infant populations, though any probiotic in this vulnerable group should only be used under medical supervision.

Bottom Line

While the broader category of probiotics has good evidence for NEC prevention in premature infants, the specific evidence for Lactobacillus reuteri is more preliminary. Many neonatal intensive care units (NICUs) that use probiotics opt for multi-strain products or strains with stronger supporting data (such as Lactobacillus rhamnosus GG or Bifidobacterium infantis). You should discuss the choice of specific probiotic strains with a neonatologist or pediatric specialist, as protocol decisions depend on local guidelines and the specific needs of the infant.

Important: This information is for educational purposes. Decisions about probiotic administration in premature infants should always be made under the direct supervision of a medical professional.