Background and Aim:

The maternal microbiome is an important determinant of neonatal immune and neurodevelopment. Microbial signatures from the mother shape fetal development and direct postnatal immune maturation. Maternal perturbations due to delivery mode, antibiotic use, diet, and metabolic status have been linked to negative birth outcomes. This review summarizes current research on how maternal factors affect the neonatal microbiome and its impact on infant immune and brain development.



Methods:

A narrative review was performed using PubMed, Scopus, and Google Scholar. English language manuscripts were identified using terms related to maternal microbiome, neonatal microbiome, pregnancy, immune development, neurodevelopment, delivery mode, antibiotic exposure, maternal diet, probiotics, and breastfeeding. Relevant human studies, systematic reviews, meta-analyses, and clinically focused reviews were included, with preference for literature published between 2015 and 2025.



Results:

Maternal influences affect how newborns acquire initial microbial communities. Vaginally delivered neonates acquire beneficial microorganisms earlier than those delivered by Cesarean section or exposed to antibiotics. Maternal nutrition, metabolic health, and breastfeeding shape the infant microbiome. Probiotic use may help restore balance, but findings vary.



Conclusion:

The maternal microbiome plays a key role in early-life development. Targeting modifications may decrease the risk of adverse neonatal outcomes, particularly in high-risk populations. Heterogeneous study designs and a lack of standardized protocols limit clinical translation. Future research should focus on longitudinal cohorts, microbial biomarkers, and well-designed trials.