Breastfeeding and Initial Gut Microbial Ecology: Impacts of GalactagogueIntervention—A Mini-Review

Introduction: The initial colonisation of the gut microbiota in infants is important for immunological and metabolic development, and breastfeeding plays a very important role with its distinctive combination of bioactive compounds. The objective of this narrative review is to consolidate knowledge about the influence of breastfeeding on early gut microbial growth and to critically assess pharmaceutical and herbal galactagogue therapies, focusing on milk composition, safety, and microbiome outcomes. Methods: Relevant publications were identified through a systematic search of Cochrane CENTRAL, PubMed, EMBASE, and Google Scholar, encompassing publications up to July–August 2025. Inclusion criteria were randomised controlled trials, cohort studies, case-control studies, and systematic reviews concentrating on breastfeeding, galactagogues, and the newborn microbiota. Data were synthesised thematically: influence of breastfeeding, mechanisms, efficacy, milk composition, population-specific effects, and safety. Results: Components of human milk, particularly human milk oligosaccharides and immunoglobulins, modulate newborn microbiota during exclusive breastfeeding. Domperidone enhances milk production; however, infant safety and long-term effects require further investigation. Herbal galactagogues such as fenugreek and moringa show small and inconsistent increases in milk volume, with limited evidence on safety and compositional alterations. Major gaps include long-term infant outcomes and data from low-resource settings. Discussion: Current evidence supports breastfeeding as a key regulator of early-life microbiome development through its bioactive matrix, but the contribution of galactagogues to microbiomerelated benefits remains unclear. Uncertain safety profiles and limited mechanistic data, particularly in diverse and low-resource populations, constrain confident recommendations and guideline integration. Conclusion: Breastfeeding effectively regulates the early microbiome, but the impact of pharmaceutical and herbal galactagogues on milk quality and infant health is still inadequately defined. Comprehensive longitudinal studies among heterogeneous groups are required to clarify benefits, risks, and tailored recommendations for galactagogues.