The findings described in the US study, also found children of obese couples had lower problem-solving ability.
The study also highlighted the effects of paternal obesity. In the past, much attention has focused on maternal health and the influence it has on the growing foetus and diagnosed disorders, such as autism.
Ages and stages align
Researchers from the National Institute of Health and Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) began recruiting more than 5,000 women, who had given birth around 4 months previously.
Here, mothers disclosed details about their health and weight — before and after pregnancy — as well as their partners' weight.
To assess development, parents completed the 'ages and stages questionnaire' (ASQ) after performing a series of activities with their children.
The ASQ was administered when the children were 4, 8, 12, 18, 24, 30, and 36 months of age.
The questionnaire is often used as a tool for assessing developmental issues in order to identify children that require additional assistance.
Compared with normal or underweight mothers (defined as a Body Mass Index (BMI) of less than 25), children of obese mothers (26% with BMI more than 30) were approximately 70% more likely to fail the fine motor assessment by age three.
Paternal obesity (29%) was associated with a 75% increased risk of failing the personal-social assessment that evaluated how well the child could interact and relate with others at the age of three.
Children at this age, whose parents both had a BMI or more than 35, were three times more likely to fail the problem-solving section of the ASQ test.
Weighty paternal influence
The study’s lead author, Dr Edwina Yeung, an investigator in NICHD’s Division of Intramural Population Health Research said the study was one that also included information about fathers, and the results suggested that the father’s weight had significant influence on child development.
With regard to a mode of action paternal obesity followed, the researchers referred to previous research in embryo development that indicated potential mechanisms that involved epigenetic alterations to sperm.
The presence of genes that could produce or have multiple effects could increase the risk of both autism spectrum disorder (ASD) and obesity, which could explain the NICHD’s observations.
Explanations as to how maternal obesity may affect offspring development are largely drawn from animal data.
“Inflammation remains a leading explanation,” the team mentioned in their discussion.
“As fat cells accumulate fatty acids and become enlarged, mechanisms respond to restrict their size, including an increase in immune cell activity. This leads to an increase in inflammatory proteins in both maternal and foetal circulation.”
The study also pointed towards interventions to counter inflammation as a possibility through dietary modification among obese pregnant women.
Published online ahead of print, DOI: 10.1542/peds.2016-1459
“Parental Obesity and Early Childhood Development.”
Authors: Edwina Yeung, Rajeshwari Sundaram, Akhgar Ghassabian, Yunlong Xie, Germaine Buck Louis