Khaberni - A new Japanese study showed that mothers experiencing severe psychological stress during or after pregnancy are at increased risk of having children with autism spectrum disorder.
Researchers at Tohoku University analyzed medical data for more than 23,000 mothers and their children, assessing symptoms of depression during the early and middle stages of pregnancy, and one month postpartum. They found that children of women who suffered from perinatal depression—a psychological distress occurring during pregnancy—were more likely to exhibit traits of autism, especially the girls who were also more prone to low birth weight, and had weaker relationships with their mothers.
However, the results showed that boys displayed traits similar to autism more than girls, regardless of their mothers' psychological condition. Researchers concluded that early diagnosis of perinatal depression is crucial to mitigate risks to the children.
To understand the biological mechanisms behind this phenomenon, the team established a stress model in pregnant mice, which showed that affected females displayed signs of depression and reduced affection.
The study reported that young female mice exhibited behaviors similar to autism, such as increased focus on personal hygiene and reduced social awareness, and that levels of oxytocin—known as the love hormone—were lower in pregnant mice, and the number of receptors in the offspring was lower, weakening the bond between mother and offspring.
The researchers confirmed that developmental delays are more common in girls with autism, highlighting the importance of supporting mothers' mental health. Nevertheless, they noted some limitations, such as the small sample size and lack of consideration for cultural differences.
These findings are consistent with a previous study published in the British Medical Journal, which found that taking antidepressants during the second and third trimesters of pregnancy nearly doubles the risk of autism in children, in a study that included more than 140,000 pregnant women. The British National Health Service explains that some mood changes are normal during pregnancy, and that prenatal depression is not rare, and includes signs such as persistent sadness, irritability, changes in eating habits, difficulty concentrating, and negative thoughts towards the child.
In related context, a recent study revealed that the likelihood of girls being diagnosed with autism might be similar to that of boys, but their diagnosis during childhood is less common, due to a lack of early diagnosis. Dr. Caroline Fife, the study's lead author, said: "Our findings suggest that the gender gap in the prevalence of autism is much smaller than previously thought, due to inadequate diagnosis or late diagnosis of women and girls."
The results were published in the journal of Molecular Psychiatry.
