Children may be more likely to develop behavior problems like attention deficit disorder if their mothers report high levels of stress and anxiety during the earlier half of their pregnancy, researchers report in the journal Child Development.
The link between anxiety and later behavioral problems is present even after accounting for factors like the baby’s birth weight and gender, mothers’ postnatal anxiety, parents’ education and influences like smoking during pregnancy, according to Bea Van den Bergh, Ph.D., and Alfons Marcoen, Ph.D., of Catholic University of Leuven, Belgium.
It’s not the fleeting moments of normal prenatal anxiety, but rather underlying levels of constant stress that seem to “enhance a child’s susceptibility for developing a childhood disorder,” Van den Bergh says.
A mother’s anxiety levels between the 12th and 22nd weeks of pregnancy were more likely than anxiety in the 32nd to 40th weeks to predict behavioral problems, the researchers found.
The 12th through 22nd weeks of pregnancy may represent a critical time in fetal development, during which stress lays down brain circuitry that could set the stage for problems like attention deficit disorder, hyperactivity, depression and aggression.
“When disturbing factors act during sensitive times in development, they impose an organization on a system that may be hard to readapt under future environments,” Van den Bergh explains.
The small study included 71 mothers and their first-born children. The women were screened for anxiety using psychological questionnaires three times during their pregnancy. None of the women in the study had been diagnosed previously with a psychiatric disorder or treated for anxiety.
Mothers, teachers and independent observers then provided information on the children’s behavioral problems when the children were 8 to 9 years old. The adults filled out internationally used, standardized clinical measurement tools, such as the Child Behavior Checklist.
Scores on the checklist indicated that 11 percent of the children in the study had at least borderline attention and hyperactivity problems, and 9 percent had at least borderline problems concerning aggression or anxiety and depression problems.
Women who reported high anxiety levels earlier in pregnancy were more apt to have children with one of these problems than those with only mild or moderate levels of prenatal anxiety.
The study was supported by the Fund of Scientific Research in Flanders, Belgium and the Population and Family Study Centre, Flemish Government.