Study decodes how grey matter in mothers’ brains undergoes changes during pregnancy

A new research shows that 94 per cent of the grey matter in the brains of mothers undergoes changes during pregnancy.

The team from Universitat Autonoma de Barcelona (UAB) found that there is a reduction and partial recovery of almost 5 per cent of grey matter in 94 per cent of the total grey matter volume of the brain, especially in regions linked to social cognition.

The study analysed the brains of women during pregnancy for the first time using neuro-imaging techniques.

The study, published in the journal Nature Communications, included non-pregnant mothers, whose partners were pregnant, to distinguish biological effects from those caused by the experience of being a mother.

Researchers from UAB, the Gregorio Maranon Health Research Institute and the Hospital del Mar Research Institute together, with other prestigious international institutions, were part of the study.

The findings reveal a dynamic trajectory in the brain during pregnancy and postpartum, significantly linked to the steroid hormone fluctuations inherent to pregnancy, and to the psychological well-being of the mothers.

The findings revealed that, during the first pregnancy, gray matter volume in the brain is reduced by up to 4.9 per cent, with a partial recovery during the postpartum period.

“These changes are observed in 94 per cent of the brain, being particularly prominent in regions linked to social cognition,” said the study.

The study also demonstrated, for the first time, that the evolution of these morphological changes in the brain is associated with fluctuations in two estrogens hormones that increase exponentially during pregnancy and return to basal levels after delivery.

The researchers observed that a greater increase and subsequent decrease in estrogen levels is associated with a greater decrease and subsequent recovery of brain grey matter volume.