Is there a link between pregnancy weight gain and autism spectrum disorders?

Researchers at the Univeristy of Utah found a link between the amount of weight a woman gains before and during pregnancy and autism spectrum disorders (ASD).  

Credit:  Emery Co Photo on Flickr

"The risk of autism spectrum disorder associated with a modest yet consistent increase in pregnancy weight gain suggests that pregnancy weight gain may serve as an important marker for autism's underlying gestational etiology," said Deborah A. Bilder, M.D., lead author of the study. "These findings suggest that weight gain during pregnancy is not the cause of ASD but rather may reflect an underlying process that it shares with autism spectrum disorders, such as abnormal hormone levels or inflammation..."

Bilder and her colleagues investigated two sample groups of children. The first group included over 120 children with ASD and a control group of over 10,000 children. All of the children were eight years old.  The second group, consisting of over 280 children with ASD, were compared to their siblings who did not have ASD.

The researchers found a pattern of pregnancy weight gain in the mothers of children with ASD.  No relationship between the mother's body mass index (BMI) at the start of pregnancy and autism was found.

"The findings in this study are important because they provide clues to what may increase the risk of having an autism spectrum disorder and provide a specific direction for researchers to pursue as they search for the causes for autism spectrum disorders," said Bilder. "Doctors have known for a long time that proper nutrition is essential to a healthy pregnancy. Pregnant women should not change their diet based on these results. Rather, this study provides one more piece for the autism puzzle that researchers are exploring."

The study, "Maternal Prenatal Weight Gain and Autism Spectrum Disorders," is published in the November edition of the journal Pediatrics.

©Mary M Conneely T/A Advocacy in Action