Effectiveness of Expressed Breast Milk Mouthwash for Infant Oral Hygiene.

Background/

Objectives

Maintaining oral hygiene in infants in neonatal and pediatric intensive care is essential for preventing ventilator-associated pneumonia (VAP). Chlorhexidine (CHX) is widely used in adults but its safety and efficacy in infants remain uncertain, and it is not recommended for children under 6 years due to rinsing difficulties and mucosal irritation risk. Expressed breast milk (EBM), rich in immunological and antimicrobial components, has been explored as a biologically appropriate alternative. This review synthesizes evidence on EBM effectiveness and safety and contextualizes it against limited indirect evidence for CHX, as no head-to-head comparative trials were identified.

Methods

A systematic search of PubMed, EMBASE, Cochrane Library, CINAHL, and Web of Science (January 2015-January 2026) identified randomized and non-randomized studies involving infants ≤ 12 months receiving EBM, colostrum, or CHX for oral care. Risk of bias was assessed using RoB 2 for RCTs and ROBINS-I for non-RCTs. Due to substantial clinical and methodological heterogeneity (differing populations, dosages, frequencies, delivery methods, and outcome definitions), a narrative synthesis was performed.

Results

Seventeen studies met inclusion criteria (11 RCTs, n = 1185; 6 non-RCTs, n > 3000). EBM and oropharyngeal colostrum were associated with trends toward lower VAP incidence trends (0-4%), reduced bacterial colonization, improved oral health indices, shorter mechanical ventilation time, and reduced ICU/hospital stays, with no reported adverse events. Evidence for CHX in infants was limited to a single paediatric RCT and bundled interventions, showing no significant VAP reduction and associations with mucosal irritation. The risk of bias was generally low to moderate.

Conclusions

Indirect evidence suggests EBM is a potentially beneficial option for infant oral hygiene, with favourable trends for infection-related outcomes and recovery parameters. However, all EBM-CHX comparisons are indirect, and CHX evidence in infants is limited by the risk of bias and heterogeneity. High-quality head-to-head randomized controlled trials are needed to determine optimal strategies and inform guidelines.