Stress during pregnancy linked to intergenerational disadvantage

New research shows stress during pregnancy is linked to impaired child brain development and can reinforce the cycle of cumulative intergenerational disadvantage.

While sociological factors such as poverty and the wider environment play a large part in intergenerational disadvantage, the research shows biological factors such as maternal mental wellbeing during pregnancy also play a role.

The evidence brief, prepared by Dr Felicia Low and Sir Peter Gluckman from Koi Tū: The Centre for Informed Futures, and Professor Richie Poulton of the University of Otago, underscores the need to rethink how the cycle of intergenerational disadvantage can be broken.

Sir Peter says: “We need to do more to support all mothers, not just those with severe clinical depression. The focus must be on women’s mental wellbeing from before pregnancy through to after birth.”

Research shows even mild to moderate stress during pregnancy can have adverse outcomes on a child’s neurodevelopment or “executive function” which impacts how a child learns.

It can have life-long consequences for a person’s journey through school and society – showing up in areas such as antisocial behaviours, school failure and poor relationships. The Dunedin Multidisciplinary Study, led by Professor Poulton, was able to predict poor outcomes from testing a child at age three.

“Children with impaired executive function may be less resilient which means they are more susceptible to stress and depression. It has a cumulative effect. Their children are likely to have a higher risk of impaired brain function and that’s how the cycle of disadvantage is reinforced,” Dr Low says.

Many women experience stress, anxiety, or depression during and after pregnancy. In New Zealand, studies suggest 12 – 18% of pregnant women are clinically depressed. An estimated 30% have less severe symptoms and consequently difficulty accessing services, as they tend to be considered lower priority than those with more severe conditions.

Stress can be further compounded by low socio-economic status. In 2019, more than 36% of children lived in a low or very-low-income household. Pregnant Māori women experience greater depression or anxiety than pregnant non-Māori women, with more than half identifying significant life stress.

The authors warn the current explosion of mental health concerns in young New Zealanders is likely to give rise to new generations of women who are at greater risk of low mood during pregnancy, further exacerbating rates of intergenerational disadvantage.

The authors suggest a formal, structured process for women to be routinely screened for depression during pregnancy.

“It is now evident that all women need support. We routinely screen for diabetes during pregnancy – we need to screen women for mental health as well,” says Dr Low.

Professor Poulton says: “Intergenerational disadvantage is arguably one of the most important social issues facing our future, and it tends to be repeated across generations in a vicious cycle.”

Sir Peter says it is indisputable that investing in disadvantaged families and young children benefits not only the children, but also successive generations, communities and society at large.

“Strengthening a child’s executive function by improving maternal mental health is arguably the most logically, morally and economically sound way of breaking the cycle of intergenerational disadvantage and advancing New Zealand,” he says.

The work was supported by the Wright Family Foundation.