MRI Study Maps Brain Growth Across the Perinatal Period - Video

The perinatal period, spanning late pregnancy and the first weeks after birth, is a critical phase for brain development. A new neuroimaging study published in Scientific Reports provides one of the most detailed views to date of how the human brain grows during this transition, using continuous prenatal-to-postnatal MRI data.

Brain development during this period involves rapid cell growth, migration, and the formation of neural connections. Most earlier studies examined either fetal or newborn brains separately, leaving a gap in understanding how the brain adapts as it moves from the womb to the outside world. This study aimed to bridge that gap.

Researchers analysed 798 MRI scans from 699 participants using data from the Developing Human Connectome Project. The dataset included both prenatal and neonatal scans, with some individuals scanned before and after birth. Brain volumes were measured between 21 and 45 weeks from conception, allowing researchers to track growth over time and compare patterns between males and females.

The study found that total brain volume increased steadily across the perinatal period, with the fastest growth occurring in late pregnancy. White matter—which supports communication between brain regions—grew rapidly in mid-gestation but made up a smaller proportion of the brain closer to birth. In contrast, gray matter growth accelerated in late pregnancy and early postnatal life, reflecting increasing development of sensory, motor, and cognitive functions.

Subcortical regions such as the thalamus and basal ganglia showed early rapid growth, while the cerebellum exhibited especially fast expansion near birth. The hippocampus grew more slowly, consistent with its role in higher-order functions that mature later in life.

Male infants had larger brain volumes overall, but growth patterns were broadly similar between sexes. Some regional differences were observed, though many appeared linked to overall brain size rather than distinct developmental pathways.

While limited by gaps in late-pregnancy and early-second-trimester data, the study offers a continuous picture of early brain growth. The findings highlight how rapidly key brain structures are established before birth and underscore the value of combining prenatal and postnatal imaging to better understand early neurodevelopment.

REFERENCE: Khan, Y. T., Tsompanidis, A., Radecki, M. A., et al. (2026). Mapping brain growth and sex differences across prenatal to postnatal development. Scientific Reports. DOI: https://doi.org/10.1038/s41598-025-33981-w. https://www.nature.com/articles/s41598-025-33981-w