Obesity before and during pregnancy has been linked with an increased risk of neurodevelopmental conditions, such as autism and ADHD, according to a new research.

ADHD, or attention deficit hyperactivity disorder, is marked by short spans of attention and impulsivity, while an autistic individual displays repetitive behaviour, often accompanied with affected social communication.

Researchers, including those from the University of South Australia, reviewed 42 studies, involving over 36 lakh mother-child pairs as participants, and found that obesity during pregnancy increases risk of ADHD in children by 32 per cent and doubles the risk of developing autism.

"Our meta-analyses demonstrated that offspring exposed to preconception overweight and obesity were at 18 per cent and 57 per cent increased risk of ADHD, respectively, when compared with non-exposed offspring," the authors wrote in the study published in the journal Psychiatry Research.

Further, being overweight or obese prior to becoming pregnant was found to heighten risk of autism by nine per cent and 42 per cent, respectively.

Obesity before pregnancy was also associated with a 30 per cent and 47 per cent increased risk of developing behavioural issues, including bullying and substance use, and troubled relationships with peer, respectively.

Maternal obesity has been studied to have adverse effects on birth outcomes, including preterm birth, low baby weight at birth and stillbirth, according to lead researcher Bereket Duko, University of South Australia.

"In this study, we examined maternal overweight and obesity before and during pregnancy, finding that both are significantly linked with psychiatric and behavioural problems in children later in life, specifically ASD, ADHD and peer relationship problems," Duko said.

With obesity rates rising among women of reproductive age around the world, and the growing incidence of neurodiverse conditions in children, the potential long-term consequences of obesity on the child's mental health need to be understood, Duko said.

The researchers said public health interventions aimed at helping prospective mothers manage weight could mitigate some of the risks of neuropsychiatric and behavioural disorders in children.

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