Association of maternal prenatal psychological stressors and distress with maternal and early infant faecal bacterial profile

Abstract Background Findings from animal studies indicate that the early gut bacteriome is a potential mechanism linking maternal prenatal stress with health trajectories in offspring. However, clinical studies are scarce and the associations of maternal psychological profiles with the early infant faecal bacteriome is unknown. This study aimed to investigate the associations of prenatal stressors and distress with early infant faecal bacterial profiles in a South African birth cohort study. Methods Associations between prenatal symptoms of depression, distress, intimate partner violence (IPV) and posttraumatic stress-disorder (PTSD) and faecal bacterial profiles were evaluated in meconium and subsequent stool specimens from 84 mothers and 101 infants at birth, and longitudinally from a subset of 69 and 36 infants at 4–12 and 20–28 weeks of age, respectively in a South African birth cohort study. Results Infants born to mothers exposed to high levels of IPV had significantly higher proportions of unclassified genera within the family Enterobacteriaceae detected at birth; higher proportions of the genus Weissella at 4-12 weeks; and increased proportions of genera within the family Enterobacteriaceae over time (birth to 28 weeks of life). Faecal specimens from mothers exposed to IPV had higher proportions of the family Lactobacillaceae and lower proportions of Peptostreptococcaceae at birth. Maternal psychological distress was associated with decreased proportions of the family Veillonellaceae in infants at 20-28 weeks and a slower decline in Gammaproteobacteria over time. No changes in beta diversity were apparent for maternal or infant faecal bacterial profiles in relation to any of the prenatal measures for psychological adversities. Conclusion IPV during pregnancy is associated with altered bacterial profiles in infant and maternal faecal bacteria. These findings may provide insights in the involvement of the gut bacteria linking maternal psychological adversity and the maturing infant brain.