Associations of maternal prenatal emotional complaints and cortisol with neonatal meconium microbiota: A cross-sectional study

The gut microbiome is a complex microbial ecosystem considered as a key modulator of human health and disease. Alterations in the diversity and relative abundances of the gut microbiome have been associated with a broad spectrum of medical conditions. Maternal emotional complaints during pregnancy can impact on offspring development by altering the maternal and the foetal gut microbiome. We aimed to investigate whether self-reported maternal anxiety, depressive symptoms, and distress as well as biological stress in late pregnancy alter the bacterial composition of the infant’s meconium. Methods A total of N =100 mother-infant pairs were included. Maternal emotional complaints were measured using standardised questionnaires (EPDS, PSS-10, STAI) at 34-36 weeks gestation and salivary cortisol was measured at 34-36 and 38 weeks gestation. Infant meconium samples were collected in the first five days postpartum and analysed using 16S rRNA amplicon sequencing. Results Correlations showed that lower alpha diversity of the meconium microbiome was significantly associated with increased maternal prenatal depressive symptoms in late gestation (τ = -0.149, p = 0.041). Increased cortisol AUCg at T2 was significantly related to higher beta diversity of the meconium samples (Pr(>F) = 0.003*). Proteobacteria was the most abundant phylum and was associated with maternal cortisol total decline. No other associations were found. Conclusions Maternal prenatal depressive symptoms are associated with infant faecal microbiota alpha diversity, whereas maternal cortisol AUCg is linked to increased beta diversity and total decline related to increased Proteobacteria . Future studies are warranted to understand how these microbiota community alterations are linked to child health outcomes. Highlights Maternal prenatal depressive symptoms alter the meconium microbiome. Increased biological stress during pregnancy alters the beta diversity of the meconium microbiome. Proteobacteria is the most abundant phylum in the meconium samples.