Maternal Perinatal Depression Linked to Autistic Traits in Toddlers, Stronger Impact on Girls, Tohoku University Study Finds
A research team from Tohoku University's Department of Psychiatry, led by Dr. Zhiqian Yu and Professor Hiroaki Tomita, has identified evidence that maternal perinatal depression is associated with an elevated risk of autistic-related traits in toddlers. Perinatal depression is defined as psychological distress experienced during pregnancy or postpartum. The study observed a particularly strong impact on girls.
Maternal perinatal depression, defined as psychological distress during pregnancy or postpartum, is associated with an elevated risk of autistic-related traits in toddlers. The study observed a particularly strong impact on girls.
Study Methodology
The findings were derived from a large-scale Japanese cohort study, the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study, which included over 23,000 mother-child pairs. Depressive symptoms in mothers were comprehensively assessed using established scales: the Kessler Psychological Distress Scale (K6) during early and mid-gestation, and the Edinburgh Postnatal Depression Scale (EPDS) at one month postpartum. Autistic-related traits in toddlers were subsequently measured by the Tokyo Autistic Behavior Scale (TABS).
To further investigate potential biological mechanisms underlying these observations, researchers also utilized a prenatal stress model in mice.
Key Findings
The study revealed a significant association between higher maternal scores on depressive symptom scales and increased autistic-related traits in toddlers. Notably, this association was more pronounced in girls. Further analyses showed that girls in the study group exhibited lower birth weights and a stronger correlation between autistic traits and impaired mother-infant bonding, as measured by the Mother-to-Infant Bonding Scale (MIBS).
In the parallel mouse model, stressed "mothers" displayed depressive-like behaviors and reduced maternal care. Their female offspring, mirroring the human study's sex-specific findings, exhibited autism-like behavioral patterns, including increased self-grooming and impaired recognition of social novelty.
Molecular analyses in the mice provided deeper insights, revealing reduced oxytocin expression in the prefrontal cortical microglia of stressed mothers. Correspondingly, a decrease in oxytocin receptor expression was found in the prefrontal cortex of their female offspring. These findings suggest a compelling sex-specific neurobiological pathway where prenatal stress may influence social development through the oxytocin system.
Implications and Limitations
The study's findings suggest that supporting maternal mental health during pregnancy may play a crucial role in reducing adverse developmental outcomes in children, particularly girls. This research provides a scientific basis for potentially sex-sensitive early intervention strategies designed to promote healthier child development.
It is important to note that the research was based on questionnaire-based measures of maternal depressive symptoms and indicators of autism-related behavioral traits, rather than clinical diagnoses of maternal depression or autism spectrum disorder. Therefore, the findings indicate an association rather than direct causation of autism spectrum disorder. Nonetheless, the study strongly emphasizes the critical importance of maternal mental health during the perinatal period.
The findings were published in the journal Molecular Psychiatry on February 4, 2026.