Study links mom’s pregnancy weight gain to baby developing ADHD, other mental disorders

CDC: More than 6 million children in America are affected by ADHD

What is ADHD? According to the National Institute of Mental Health, the initials ADHD stand for attention-deficit/hyperactivity disorder. It's a brain disorder marked by an ongoing pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. Some of the symptoms include impulsivity, hyperactivity and inattention. Conditions common in people who have ADHD include learning disabilities, anxiety disorder, conduct disorder, depression and substance abuse.

More than 6 million children in America are affected by ADHD, according to the Centers for Disease Control and Prevention. Yet, two new studies show how birth conditions may increase the likelihood of developing this mental disorder.

A recent study published in the Journal of Clinical Endocrinology & Metabolism found women with gestational weight gain and diabetes were two times more likely to give birth to a child with ADHD than mothers without obesity. From 1991 through 2008, the researchers studied 1,036 children whose mothers had gestational diabetes and weight gain.

Of those children, 13% were diagnosed with ADHD. Although a mother’s weight gain played a role in the likelihood of children developing mental health problems, the risk didn’t occur if the weight gain stayed within a healthy range, the study showed.

“Our study found pregnant women with obesity and gestational diabetes had children with long-term mental health disorders such as ADHD,” lead author of the study, Verónica Perea, M.D., Ph.D., said in a press release. “We did not find this association when these women gained a healthy amount of weight during pregnancy.”

Another study, published in the Journal of Pediatrics, found children born before 39 weeks are more likely to report symptoms associated with ADHD. The researchers collected data on 1,400 9-year-old students from their teachers. The teachers evaluated their students using a scale that indicates symptoms of ADHD. The results of the study found that children who were born at 37-38 weeks scored 23% higher in hyperactivity and 17% higher in ADHD compared to the children born at 39-41 weeks.

“The findings add to growing evidence supporting current recommendations for delaying elective deliveries to at least 39 weeks and suggest that regular screenings for ADHD symptoms are important for children born at 37 to 38 weeks,” study author Nancy Reichman said in a press release. “Significant growth and development in various kinds of brain cells are observed between 34 and 40 weeks of gestation. Infants born at full-term likely benefit from the additional one to two weeks of brain growth in utero compared with those born early-term.”

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