Maternal perinatal depression linked to autistic traits in toddlers

New research suggests a link between maternal psychological distress during and after pregnancy and the development of autistic-related traits in toddlers, with girls appearing particularly vulnerable. A study led by Dr. Zhiqian Yu and Professor Hiroaki Tomita at the Department of Psychiatry at Tohoku University analyzed data from over 23,000 mother-child pairs and was supported by experiments with mice.

Understanding the Connection

Researchers assessed mothers for depressive symptoms during early and mid-gestation, and again one month after childbirth, using the Kessler Psychological Distress Scale (K6) and the Edinburgh Postnatal Depression Scale (EPDS). Higher scores on these scales were associated with increased autistic-related traits in toddlers, as measured by the Tokyo Autistic Behavior Scale (TABS). This association was notably stronger in girls.

Did You Know? The study utilized data from the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study, a large-scale Japanese research initiative.

The study also revealed differences in girls, who exhibited lower birth weights and a stronger connection between autistic traits and difficulties in mother-infant bonding, as measured by the Mother-to-Infant Bonding Scale (MIBS).

Exploring the Biological Mechanisms

To investigate the underlying biological factors, researchers conducted experiments using mice. Mice experiencing prenatal stress displayed depressive-like behaviors and reduced maternal care. Their female offspring showed behaviors similar to autism, including increased self-grooming and difficulty recognising social cues.

Molecular analysis revealed reduced levels of oxytocin – often called the “love hormone” – in the prefrontal cortical microglia of stressed mothers. The female offspring of these mothers also showed decreased oxytocin receptor expression in their prefrontal cortex. This suggests a potential pathway where prenatal stress disrupts social development, particularly in females, through alterations in the oxytocin system.

Expert Insight: These findings underscore the critical role of maternal mental health during pregnancy and the postpartum period. recognising and addressing psychological distress in mothers could have significant implications for the neurodevelopment of their children, and potentially lead to more targeted interventions.

The researchers emphasize that this study does not demonstrate a direct causal link between maternal perinatal depression and autism spectrum disorder. Instead, it highlights the importance of supporting maternal mental health, given the potential for sex-specific effects on children’s emotional and developmental outcomes.

Frequently Asked Questions

What did the study measure in mothers?

The study assessed depressive symptoms during early and mid-gestation and at one month postpartum using the Kessler Psychological Distress Scale (K6) and the Edinburgh Postnatal Depression Scale (EPDS).

Was this study conducted only with humans?

No, the study included both a large-scale analysis of over 23,000 Japanese mother-child pairs and experiments conducted with mice.

Did the study find the same results for boys and girls?

While an association was found for both sexes, the risk associated with maternal perinatal depression was especially pronounced in girls, who also showed lower birth weights and a stronger link between autistic traits and impaired mother-infant bonding.

How might supporting maternal mental health impact future generations?