In a 2017 Nature Neuroscience study, researchers scanned the brains of 25 women before their first pregnancy and after birth, and compared them with 20 women who had not given birth. Pregnancy was linked to a reduction in grey matter volume in areas important for social cognition, such as understanding what others are thinking. The changes were so clear that an algorithm could identify every woman who had been pregnant from them alone. No similar changes were found in fathers, and about two years later most of the changes were still visible.
The brain tunes in to the baby
In 2020, the same group found that pregnancy also reduces the volume of the ventral striatum, part of the reward system. The more it shrank, the more strongly it responded after birth when mothers looked at photos of their own baby. A 2024 study that followed one woman week by week also showed a reduction in grey matter and an increase in white matter integrity.
Researchers interpret these changes as adaptation to a new role, not a loss of ability.
What this means for you
- Changes after birth are a natural adaptation of the brain, not “mental decline”.
- Strong sensitivity to your baby’s signals has a biological basis.
- If you feel sad or anxious for a long time after giving birth, seek help: postpartum depression is treatable.
Sources
- Hoekzema E., Barba-Müller E., Pozzobon C. et al. (2017). Pregnancy leads to long-lasting changes in human brain structure. Nature Neuroscience, 20, 287–296. doi:10.1038/nn.4458
- Hoekzema E., Tamnes C. K., Berns P. et al. (2020). Becoming a mother entails anatomical changes in the ventral striatum of the human brain that facilitate its responsiveness to offspring cues. Psychoneuroendocrinology, 112, 104507. doi:10.1016/j.psyneuen.2019.104507
- Pritschet L., Taylor C. M., Cossio D. et al. (2024). Neuroanatomical changes observed over the course of a human pregnancy. Nature Neuroscience, 27(11), 2253–2260. doi:10.1038/s41593-024-01741-0