Antidepressants taken by 400,000 US pregnant women each year can damage a baby’s brain in the womb and increase their risk of mental health problems in the future, study suggests

Using antidepressants during pregnancy or while breastfeeding can damage a baby’s brain and increase their risk of suffering mental health problems in the future, a study found.

Prozac, also known as fluoxetine, increases levels of mood-boosting serotonin in the brain – but scientists discovered this can affect a child’s developing prefrontal cortex.

They also found the drug can pass into the breast milk of new mothers who take it and end up being fed to newborns. 

Research suggest that between 300,000 and 400,000 kids are being exposed to Selective Serotonin Reuptake Inhibitor (SSRI) drugs each year in the US during pregnancy. 

Professor Won Chan Oh, of the University of Colorado, said: ‘We are the first to provide experimental evidence of the direct impact of serotonin on the developing prefrontal cortex when fluoxetine is taken during pregnancy.

‘While it is known that serotonin plays a role in brain development, the mechanisms responsible for this influence, specifically in the prefrontal cortex, have been unclear.

‘Understanding this has the potential to help with early intervention and the development of new therapeutics.’

The researchers said doctors should consider non-pharmaceutical treatments for pregnant women and those suffering from postnatal depression.

Serotonin is involved in overall brain function but also influences how connections between neurons change and adapt, contributing to the brain’s ability to learn and adjust.

The prefrontal cortex is the most evolved brain region and plays a central role in various high-level functions, including planning, decision-making, problem-solving and personality expression.

The new study, published in Nature Communications, looked at the impact of deficiency and surplus of serotonin on brain development in mice.

The researchers now plan to examine the impact of Prozac on a developing teenage brain.

Prozac is one of the world’s most prescribed antidepressants. It is available on the NHS and is often used because it has fewer side effects than other drugs.

Antidepressants are on the rise in the UK, with 86million prescribed in 2022/23 to an estimated 8.6million patients – 200,000 more than the year before.

Earlier this week, a separate study found that exercise and yoga may be just as effective as pills to alleviate depression.