Impact of Prenatal Air Pollution Exposure on Fetal Brain Development

Recent research conducted by the Barcelona Institute for Global Health (ISGlobal), in collaboration with the BCNatal center and the Hospital de la Santa Creu i Sant Pau, has revealed that exposure to air pollutants during pregnancy can influence fetal brain structures. The study, published in The Lancet Planetary Health, focused on how prenatal exposure to pollutants such as nitrogen dioxide (NO₂), particulate matter (PM₂.5), and black carbon affects brain development during gestation.

The study analyzed data from 754 mother-fetus pairs within the Barcelona Life Study Cohort (BiSC) between 2018 and 2021. Researchers utilized advanced models that combine real measurement data with statistical techniques to estimate air pollution exposure in three microenvironments: a woman's home, workplace, and commuting routes. Participants' activity patterns were tracked via geolocation apps.

Findings indicated that higher prenatal exposure to these pollutants correlates with increased volumes in certain brain cavities filled with cerebrospinal fluid. Notably, the lateral ventricles in both brain hemispheres and the cisterna magna showed enlargement. Additionally, the width of the cerebellar vermis, crucial for motor control and balance, was also found to be wider in fetuses with higher pollution exposure.

Another significant observation was that increased black carbon exposure was associated with a reduction in the depth of the lateral sulcus, hinting at possible impacts on brain maturation. The strength of these associations was more pronounced during the second and third trimesters, a critical period for fetal brain development.

Dr. Payam Dadvand from ISGlobal emphasized that during mid to late pregnancy, the fetal brain undergoes vital growth phases, making it particularly susceptible to external factors like pollution. Experts from hospitals involved in the study highlighted that even pregnancies that appear healthy can be subtly affected by environmental exposures, underscoring the importance of awareness and preventive measures.

While these brain structure differences are currently within normal ranges, they could indicate increased vulnerability to neurodevelopmental issues later in life. Researchers stress the need for further studies to determine if these changes are reversible or have long-term consequences. Overall, this research advocates for public health policies aimed at reducing pregnant women’s exposure to harmful air pollutants, especially in urban environments.

Source: https://medicalxpress.com/news/2025-06-exposure-pollution-pregnancy-linked-fetal.html