Heightened inflammation during pregnancy may increase the risk of mental illness or brain development problems in children, according to a new study led by researchers at Oregon Health & Science University (OHSU) in Portland.
The research team discovered a link between inflammation in pregnant women and the way the newborn brain is organized into networks. The findings, published in the journal Nature Neuroscience, may offer promising avenues for treating such negative impacts on newborn brain function.
The research team, led by Damien Fair, P.A.-C., Ph.D., associate professor of behavioral neuroscience and psychiatry in the OHSU School of Medicine, and Claudia Buss, Ph.D., of the Charité-Universitätsmedizin in Berlin, Germany, and associate professor at University of California Irvine, collected blood samples from 84 pregnant women at each pregnancy trimester.
The samples were measured for levels of the cytokine interleukin-6, or IL-6, an inflammatory marker known to play a role in fetal brain development.
Four weeks after delivery, the infants’ brain connectivity patterns were evaluated using functional magnetic resonance imaging (fMRI) scans. At age 2, the children were also tested for working memory performance, a key skill that supports academic achievement and is frequently compromised in mental health disorders.
The findings reveal that differences in the levels of inflammatory markers are directly associated with differences in newborn brain communication, and later to working memory scores at age 2. Higher levels of the marker during pregnancy were more likely to result in poorer working memory in the child.
“Importantly, this doesn’t mean that every exposure to inflammation will result in a negative impact to the child,” said co-author Alice Graham, Ph.D., postdoctoral fellow in behavioral neuroscience in the OHSU School of Medicine.
“However, these findings provide new avenues for research, and can help health care providers think about how, and when, inflammation might impact a child’s long-term learning development and mental health.”
A notable aspect of the study was the development of a model that can correctly estimate information about maternal inflammation during pregnancy based only on newborn brain functioning, said Graham. Created using artificial intelligence known as machine-learning, the model is based on the biomarkers identified in the study and can be applied to cases beyond the initial research.
“Now, we have an approach that can utilize MRI brain scans of a newborn to accurately estimate the mother’s overall levels of inflammation during the time of her pregnancy,” she said. “This understanding provides some information about future memory function of that child approximately two-years later, creating a potential opportunity for research surrounding early clinical intervention, if necessary.”
According to Fair, future research should focus on how factors before and after birth — such as society and environment — interact to influence brain function and cognition in newborns.
“Increased stress and poor diet are considered normal by today’s standards, but greatly impact inflammation rates in all humans, not just expectant mothers,” said Fair. “Just as important to understanding how the immune system and inflammation affect early brain development, we also need to understand what common factors contribute to heightened inflammation so that we may target therapies to help reduce the rates of inflammation and overall impact on the developing brain.”