While genetic factors are clearly important in determining a child’s risk for attention deficit hyperactivity disorder (ADHD), recent studies have investigated the link between exposure to certain maternal behaviors during pregnancy, such as smoking and alcohol use, and the risk of developing behavioral problems related to attention deficit hyperactivity disorder in childhood. While multiple studies have indicated a greater risk of ADHD symptoms among children whose mothers smoked during pregnancy, contradictory findings were reported in studies focusing on exposure to alcohol. Results from studies investigating the impact of psychological stress during pregnancy have been inconsistent but suggest a possible contribution to ADHD symptoms int he offspring.
In a recent study conducted at McGill University, researchers examined whether there is an association between the severity of maternal stress during pregnancy and the severity of ADHD symptoms in their offspring.203 children with ADHD (6 to 12 years of age) were identified, and ADHD symptom severity was assessed using the Child Behavior Checklist (CBCL) and Conners’ Global Index for Parents (CGI-P) and Teachers (CGI-T). The Kinney Medical and Gynecological Questionnaire was used to assess pre-, peri- and postnatal complications, including stressful life events, in the mothers.
The most severe ADHD symptoms were found among children whose mothers experienced moderate to severe stressors during pregnancy as compared to children whose mothers experienced no significant stressors. In addition, it was noted that the children exposed to higher levels of maternal stress were also more likely to exhibit mood symptoms and anxiety. When the researchers compared the effects of stressors in each trimester on symptom severity, they found that increased stress during the third trimester correlated with greater severity of ADHD symptoms.
There is an increasing awareness that maternal depression and anxiety experienced during pregnancy may have negative effects on the developing fetus. While this study does not specifically assess for depression or anxiety in the mother, it suggests that exposure to stressors can also have a negative impact. This study not only underscores the importance of minimizing stress during pregnancy but suggests that it may be beneficial to screen for symptoms of psychological distress in pregnant women.
Ruta Nonacs, MD
Read More on this Topic:
BBC News: Stress ‘harms brain in the womb’