Chronic mild stress in pregnant mothers may increase the risk that their offspring will develop cerebral palsy – a group of neurological disorders marked by physical disability – according to new research in mice. The results may be the first to demonstrate such effects of stress on animals in the womb.

The new study, led by Pierre Gressens, MD, PhD, of Inserm in France, used a mouse model to test whether exposure to minimal but repeated stress throughout gestation would make the offspring more vulnerable to brain lesions similar to those observed in children with cerebral palsy. The findings are published in the July 11 issue of the Journal of Neuroscience. Inserm, l’Institut national de la santé et de la recherche médicale, is the French public biomedical research agency.

“These findings are consistent with growing evidence that constant stress, even minimal, can have a major impact on the quality of life,” says Victoria Luine, PhD, distinguished professor of psychology at New York’s Hunter College, who did not participate in the research.

In the study, the scientists adjusted the normal cycle of light and dark that the pregnant mice were accustomed to for half of the mice, subjecting them to a mild level of stress. Then the researchers exposed the brains of the developing fetuses to injury. When the brains of the young mice were examined on birth, Gressens and his team found that the offspring born from stressed mothers showed brain lesions about twice as big as those in offspring of unstressed mothers.

“Determining the impact of gestational stress on the incidence of cerebral palsy would be of paramount interest,” says Gressens. “Limiting stress during human pregnancy might prove to be a cost-efficient way to reduce the human, emotional, social and economic burden of cerebral palsy.”

– Society for Neuroscience