The role of the maternal gut microbiome in regulating endocrine function during pregnancy and postpartum: implications for neonatal health

Objective: This systematic review aims to examine the role of the maternal gut microbiome in regulating endocrine function during pregnancy and the postpartum period, and its effects on neonatal health. Additionally, it assesses the effectiveness of microbiome-targeted interventions and identifies knowledge gaps in the current literature to inform future research directions. 
Design and Methods: A systematic literature review was conducted following PRISMA 2020 guidelines. Searches were performed in PubMed, Scopus, and the Cochrane Library. Out of 94 identified records, 19 studies met the inclusion criteria based on the PICOST framework. The included studies were critically appraised using the Caldwell framework. 
Results: Findings indicate that metabolites derived from the maternal gut microbiome influence maternal endocrine function, affecting maternal weight and neonatal outcomes such as birth weight and length. Specific microbial profiles were found to predict gestational age and neonatal development, while some were linked to excessive fetal growth. In cases of gestational diabetes mellitus, notable dysbiosis was observed in both mothers and their newborns, with significant implications for health. The use of probiotics showed mixed results, beneficial in some studies, ineffective in others. 
Conclusion: The maternal gut microbiome plays a critical role in maternal and neonatal health by interacting with the endocrine system and influencing key developmental outcomes. However, this emerging field remains under-researched. Further longitudinal and mechanistic studies are needed to clarify causal pathways and to evaluate the clinical utility of microbiome-based interventions during pregnancy.