Data published in EBioMedicine indicated that increased maternal alpha diversity during pregnancy was associated with a reduction in internalizing symptoms in children at two years of age.
In addition, researchers reported that butyrate-producing families of bacteria called Lachnospiraceae and Ruminococcaceae were more abundant in moms of kids with “normative behavior”.
“This is the first human study to investigate the relationship between maternal fecal microbiota during pregnancy and behavioral outcomes in children,” wrote the researchers, led by Professor Peter Vuillermina from Deakin University in Australia.
“Our findings support the evidence from animal studies and suggest that there may be a developmental window during pregnancy where aspects of the maternal prenatal gut microbiota influence fetal brain development, and in turn, behavior in offspring,” they added.
Prof Vuillermina and his co-workers analyzed data from 213 mothers and 215 children participating in the Barwon Infant Study (BIS), and behavioral outcomes of the children were assessed at two years of age using the Childhood Behavior Checklist.
The data indicated an association between the alpha diversity of the mother’s fecal microbiota during the third trimester and reduced internalizing behavior in the child. However, there was no evidence of a link between prenatal alpha diversity and externalizing behaviors, said the researchers.
In addition, an association was observed between a higher maternal abundance of Lachnospiraceae and Ruminococcaceae families of the Clostridia class and normative behavior in the children.
“A recent murine study demonstrated that colonizing microbiota-depleted dams prior to conception prevented neurodevelopmental abnormalities,” wrote the researchers, referring to a study with mice by Vuong et al. published last year in Nature. “In particular, colonization with taxa from the Clostridia class prevented sensory behavioral disturbances in offspring and elevated metabolites involved in axonogenisis in the maternal sera and fetal brain. Although the Clostridia taxa identified in the current study differed from those identified the murine study, it is possible that similar mechanistic pathways are relevant.”
“The association between higher maternal carriage of the butyrate producers Lachnospiraceae and Ruminococcaceae (to which most key butyrate-producing species belong), and children with improved behavior is consistent with the mounting evidence that butyrate is neuroprotective,” they added.
Barwon Infant Study
The new study adds to earlier data from this cohort, which was also published in EBioMedicine. That paper reported that children with lower levels of Prevotella at one year of age one are more likely to have anxiety-like behaviors at two, including shyness, sadness, and an internal focus.
In the new study, the researchers considered if the link between the mother’s microbiota and child behavior is mediated by the infant microbiota, but there was no evidence to support this, they said.
“The lack of association may be because the infant gut microbiota is still developing and, until three years of age, is far less diverse,” they wrote. “Nevertheless, our current evidence is more compatible with an in utero effect rather than a postnatal effect.
“Further human studies are required to replicate these findings and delineate the underlying mechanisms,” they concluded.
Source: EBioMedicine, published by The Lancet
Volume 68, 103400, doi: 10.1016/j.ebiom.2021.103400
“Maternal prenatal gut microbiota composition predicts child behavior”
Authors: S.L. Dawson et al.