Stress during pregnancy may change brain development in babies 

Infants’ brains may be shaped by the levels of stress their mothers experience during pregnancy, a new CVS and CRH study has revealed. 

Black and white photo of pregnant woman

Stress in pregnant mothers – measured through levels of the stress hormone, cortisol – have been linked to changes in infant brain development of the amygdalla, which is involved in children’s social and emotional development. 

The recent findings highlight the need for better mental support for pregnant mothers, to help alleviate and manage stress, protecting both mothers’ health and children’s development.

Thankfully, psychological treatments are very successful at helping mothers and children and we hope that our findings could guide therapies in future to help spot those who might be most in need of support.

Professor Rebecca Reynolds
Personal Chair of Metabolic Medicine, Centre for Cardiovascular Science, who co-led the study

Measuring Stress

This new study offers an objective connection between stress and a child’s ability to regulate emotions. While the link between maternal stress and infant development has been studied before, previous studies have used questionnaires to assess maternal stress levels, which can result in subjective self-assessments. This study uses cortisol measurements to offer the first objective look at the relationship between stress and infant brain development.  

Cortisol is a stress hormone that helps regulate blood pressure, sleep cycles, and mood. It has also been linked to anxiety and other health problems, and has previously been shown to play a role in foetal growth. Higher cortisol levels indicate higher stress on the body. 

The Study

The study, from researchers within the University of Edinburgh’s Centres for Reproductive Health and Cardiovascular Science, measured cortisol levels in hair samples from 78 volunteer pregnant women. These women’s newborn babies later underwent several non-invasive MRI brain scans - all while fast asleep - to examine their brain development. 

The scientists found a link between higher cortisol level’s in the volunteer mums’ hair and structural changes in their babies’ brains. They also noticed different brain connections and amygdalla formation associated with the higher cortisol levels. 

While the study did not directly assess emotion in children, this newly discovered link could provide an explanation for why children of mums who experience high levels of stress may be more likely to develop emotional issues later in life. 

Our findings are a call to action to detect and support pregnant women who need extra help during pregnancy as this could be an effective way of promoting healthy brain development in their babies. 

Professor James Boardman
Lead researcher, Director of the Jennifer Brown Research Laboratory at the MRC Centre for Reproductive Health

The experts add that pregnant women who feel stressed or unwell should seek help from their midwife or consultant. With support, most health issues can be well managed in pregnancy. 

The study was funded by the global children’s charity, Theirworld, and is published in the journal eLife.

Related Links

Research Article

Professor Rebecca Reynolds

Professor James Boardman

MRC Centre for Reproductive Health