Babies of stressed pregnant mums may have lasting effects

By Dr. Ananya Mandal, MDJul 20 2011

According to a new study high levels of stress during pregnancy can cause an unborn child to have lifelong mental scars. Researchers have found that a mother facing unnecessary crises can leave an imprint in the brains of her children, making them less able to cope as they get older.

The team asked 25 mothers whether they had suffered extreme stress caused by abuse from boyfriends or husbands while they were pregnant, and then rated their emotional level. They then monitored the behavior of a particular gene in their children, who were aged nine to 19.

The gene – called the glucocorticoid receptor – is involved in the brain’s response to stress. The German researchers found that the gene was far less active in children whose mothers were victims of domestic abuse when they were pregnant. Abuse after pregnancy did not appear to affect the way the gene responded in the brains of their children.

According to researcher Helen Gunter, of the University of Konstanz, “It changes the way that people respond to stress and they may have a reduced ability to respond to stress… Past studies have shown that children who have abused parents are more prone to depression later in life.” However she warned, “We did not look at the everyday stresses of working or having a family. This study is very specific to abuse.”

The report appears in journal Translational Psychiatry. Dr Gunter said the study looked only at the extreme stress caused by partner violence.

Dr Carmine Pariante, of the Institute of Psychiatry at Kings College London, said, “This paper confirms that the early foundation years start at minus nine months. We have known for some time that maternal stress and depression during pregnancy induce a unique response in the offspring, by affecting children’s behavior well into adolescence and children’s ability to modulate their own stress response. This study shows that the glucocorticoid receptor, that is, the receptor for stress hormones, is subject to a key biological change that contributes to the organization of this offspring response. This confirms that pregnancy is uniquely sensitive to a challenging maternal psychosocial environment – much more than, for example, after the baby is born. As we and others have been  advocating, addressing maternal stress and depression in pregnancy is a clinically and socially important strategy.”

Thomas Elbert, who is a professor of neuropsychology and clinical psychology at the University of Konstanz, says revolutionary developments in the field of gene sequencing should lead to a much better understanding of how prenatal exposures alter gene expression, behavior, and even susceptibility to disease. “Now that we can sequence full genomes relatively cheaply there is no telling what we will find…I do believe we will know a lot more in the next two or three years than we know today, the findings also emphasize the importance of domestic violence interventions that target women in their childbearing years,” he said.