A parent’s weight can affect the early development of a child, and researchers now consider parental obesity – either a mother’s or father’s – as a risk factor for severe developmental delays, says a new study.
Specifically, children of obese parents have a significantly greater risk of lagging behind their peers in developing fine motor skills and also face a diminished capacity for social intelligence, according to the study from researchers with the National Institute of Child Health and Human Development (NICHD).
The study, published in Pediatrics online, adds another layer to the growing body of evidence that links parental obesity to neurodevelopmental issues in children.
“The previous U.S. studies in this area have focused on the mother’s pre- and post-pregnancy weight,” said study author Dr. Edwina Yeung, an investigator in NICHD’s Division of Intramural Population Health Research. “Our study is one of the few that also includes information about fathers, and our results suggest that dad’s weight also has significant influence on child development.”
By age 3, children with obese mothers were 70% more likely “to have failed the test indicator on fine motor skills,” according to the study. Fine motor skills are tasks that can be performed with precise movements, such as picking up a needle with the forefinger and thumb.
Also by age 3, children of obese fathers had a 75% increased chance of failing a personal-social test, which is “an indicator of how well they were able to relate to and interact with others.”
The researchers also found that children with two obese parents were three times as likely to fail a problem-solving test than other children.
How It Happened, and What It Means
The researchers drew their conclusions from a large study that enrolled about 5,000 women in upstate New York who had given birth within the previous four months. The study collected weight and height information of the parents that the researchers used to determine each parent’s body mass index (BMI).
The research team then used a screening tool called the Ages & Stages Questionnaire to assess the children’s development over a three-year period. In all, they conducted seven tests on the children, with the first one occurring at 4 months of age and continuing through the age of 3.
The reduction in fine motor skills among parents of obese mothers was similar among boys and girls, and the researchers noted a “significant increased risk of failing the personal-social domain” among all children – excluding twins – of obese fathers.
While the evidence is alarming, the reasons behind the slower development among children of obese parents remain something of a mystery. Animal studies suggest that inflammation, more prevalent among those with a higher BMI, may be to blame. Other studies suggest that changes to a father’s sperm “could have downstream impact,” according to the study.
While future studies may shed more light on the exact cause-and-effect relationship, the current results cast an ominous light on the health of the population – about one in five pregnant women is obese, report the study authors.
The “findings emphasize the importance of family information when screening child development as, if replicated elsewhere, such information may help inform closer monitoring or earlier intervention,” conclude the researchers.