Stress in expectant mothers could result in poor brain development in their unborn children
About nine out of every 1,000 babies born in the US have a congenital heart defect, according to the American Heart Association. Now a study has found that a high percentage of pregnant women with a diagnosis of a major fetal heart problem tested positive for stress, anxiety and depression.
About 65% of pregnant women expecting a baby with congenital heart disease (CHD) are stressed, finds a study. This could result in poor brain development in their unborn children, with brain regions linked to memory, learning, movement, social and behavior taking a beating.
These findings suggest that identifying stressed out expectant mothers is crucial to helping them receive the much-needed support. Further, universal screening for psychological distress must become a part of prenatal care, say the authors of the study.
"We were alarmed by the high percentage of pregnant women with a diagnosis of a major fetal heart problem who tested positive for stress, anxiety and depression," says Dr. Catherine Limperopoulos, director of the Center for the Developing Brain at Children's National and the study's corresponding author.
CHD is a condition occurring before birth: the fetus shows abnormal development of heart, or blood vessels near the heart. About nine out of every 1,000 babies born in the US have a congenital heart defect, according to the American Heart Association. Shortly after birth, some babies turn blue or have very low blood pressure. Some children with the condition face breathing difficulties, feeding problems or poor weight gain.
To study the link between maternal stress and brain development in the fetus, the team included 48 women whose unborn fetuses had been diagnosed with CHD. The team measured the prevalence of stress and anxiety among the 48 women and compared these results with 92 other healthy women with uncomplicated pregnancies.
The team found that among pregnant women expecting a baby with CHD, about 65%, 44% and 29% of them tested positive for stress, anxiety and depression, respectively. And among those with uncomplicated pregnancies, only 27%, 26% and 9% showed stress, anxiety and depression, respectively.
In their next experiment, the team looked at fetal brain size using sophisticated imaging technologies such as magnetic resonance imaging. The size of fetuses' brains were then matched with their mothers' stress scores.
The results showed that stressed out pregnant women had fetuses with smaller brain regions: the hippocampus and cerebellum. The hippocampus is key to memory and learning, while the cerebellum controls motor coordination and plays a role in social and behavioral development.
"None of these women had been screened for prenatal depression or anxiety. None of them were taking medications," Dr. Limperopoulos adds. The study included educated women, 81% of these women had attended college and 75% had professional education. Lack of resources, according to the authors, may not be driving these results.
"It is critical that we routinely to do these screenings and provide pregnant women with access to interventions to lower their stress levels," Dr. Limperopoulos explains.
The study does not explain how exposure to maternal stress impacts brain development in fetuses with CHD.
In the future, the team is interested in coming up with psychological strategies to help these mothers. "Our next goal is exploring effective prenatal cognitive behavioral interventions to reduce psychological distress felt by pregnant women and improve neurodevelopment in babies with CHD," says Dr. Yao Wu, a research associate working with Limperopoulos at Children's National and the study's lead author.
The study has been published in JAMA Pediatrics.