A joint study by Hospital del Mar, the Barcelona Institute for Global Health, and the Center for Epidemiological and Public Health Research showed that maternal exposure to high levels of fine particulate matter (PM2.5) during pregnancy slows the myelination process in their newborns' brains, a vital process that coats nerve connections with myelin to enhance the efficiency of information transmission.
This study is the first of its kind to focus on analyzing brain development during the first month of life. The researchers warned that any disruption in the pace of brain maturation, whether excessive slowing or abnormal acceleration, could negatively impact children's neurological health and cognitive abilities later in life.
"Our study conclusively shows that myelination, a biomarker of brain maturation, occurs at a slower rate in infants exposed to higher levels of air pollution during pregnancy," explained researcher Gerard Martinez-Villavilla of the MRI unit at Hospital del Mar.
These tiny particles are extremely small, with a diameter approximately thirty times smaller than the thickness of a human hair. They consist of a mixture of harmful elements resulting from combustion and toxic organic compounds, along with essential elements such as iron, copper, and zinc, which play important roles in brain development.
The study followed a group of pregnant women at three major hospitals in Barcelona. 132 newborns underwent advanced MRI scans during the first month to assess their brain maturity by measuring the progress of the myelination process.
The results showed a clear link between increased exposure to fine particulate matter during pregnancy and decreased myelination in the brain. "These findings are a wake-up call to redouble our efforts to improve air quality in our cities, especially given the inadequacy of current measures to meet the required air quality standards," said researcher Jordi Suner of the Barcelona Institute for Global Health.
The study opens new avenues for understanding the optimal pace of brain maturation during pregnancy, the role of the mother and placenta as a natural line of defense protecting the fetus's neurodevelopment, and highlights the need to control air pollution to protect the health of future generations.
