Stressed mothers have uncoordinated children, according to WA research which links emotional trauma during pregnancy to poor motor function.

PERTH, AAP - Stress during pregnancy may lead to poor co-ordination in children, West Australian research suggests.

Almost 3000 mothers were asked to record stressful incidents in their pregnancies at 18 and 34 weeks.

Their children then underwent a series of co-ordination tests through their childhoods.

The University of Notre Dame study found children born to mothers who experienced more stressful events during pregnancy scored lower in motor development.

Children with the poorest motor function were born to mothers who had recorded three or more stressful events during pregnancy.

"This may suggest an accumulative effect of stress on the developing fetal motor system, with small amounts of stress having a negligible effect and greater amounts having a negative effect," the study said.

Low motor development has been linked to poorer mental and physical health.

Human movement professor Beth Hands said it was important for mothers to be emotionally healthy during pregnancy.

"Detecting and reducing maternal stress during pregnancy may alert parents and health professionals to potential difficulties and improve the long-term outcomes for these children," Prof Hands said.