The Mother’s Microbiota Can Influence Fetal Development

The Mother’s Microbiota Can Influence Fetal Development

During pregnancy, the expectant mother not only transfers nutrients to her baby but also transmits microbes. Finnish researchers have discovered that the mother’s microbiota influences gene expression in the placenta, brain, and fetal intestine in mice.


A recent Finnish study published in BMC Biology suggests that maternal microorganisms are crucial for offspring development and health. Significant differences in gene activity were found in the fetus’s placenta, brain, and intestine based on the microbes present in the mother’s body.

The research also revealed new metabolites believed to be influenced by the maternal microbiota. “We identified previously unknown compounds in the foetus, which are likely to be microbial, and which can be important for individual development,” stated Mikael Niku, a researcher at the Faculty of Veterinary Medicine at the University of Helsinki. According to the authors, many potentially important metabolites remain to be identified.

Male Fetuses Are More Affected

Researchers compared fetuses from normal mice to those from germ-free mice (lacking microbiota) living in a sterile environment. They measured gene expression and metabolite concentrations in the fetus’s intestine, brain, and placenta. For instance, genes in the intestine associated with the immune system were less active in fetuses from germ-free mothers. Differences were observed in the expression of brain genes related to the development and functioning of the nervous system.

In the placenta, genes encoding prolactin and other essential pregnancy regulators were downregulated in germ-free mothers. Furthermore, male fetuses exhibited more differences, suggesting they might be more sensitive to the effects of maternal microbiota, at least in mice.

This research could contribute to understanding why some babies are predisposed to immune system dysfunctions, such as inflammatory bowel diseases and allergies.

Featured Image: Mikael Niku, The molecular models in the image made using QuteMol.