Maternal microbiota and fetal brain development: a multidisciplinary review of cognitive, neurological, and metabolic outcomes

Objective

The prenatal period represents a critical window for the programming of the central nervous system. This multidisciplinary narrative review aims to synthesize current evidence regarding the maternal microbiota-gut-fetal brain axis, examining how maternal gut composition may influence fetal neurogenesis, synaptogenesis, and long-term neurobehavioural outcomes. Mechanism: We analyse three primary pathways of influence: the systemic translocation of neuroactive bacterial metabolites (specifically short-chain fatty acids), the modulation of the maternal immune system leading to maternal immune activation (MIA), and the endocrine regulation of the hypothalamic-pituitary-adrenal axis. These pathways are interconnected and their synergistic effects are considered throughout.