A new study carried out at the Kaiser Permanente Southern California Department of Research and Evaluation has shown that children may be at a higher risk of developing autism if their mother has received a diabetes diagnosis before the 26th week of their pregnancy.
Women who were diagnosed with diabetes early in their pregnancy were 42% more likely to give birth to a child who would be later diagnosed with autism. The study, which involved over 322,000 children born between 1995 and 2009, found that about 1% of these children received an autism diagnosis before they reached the age of six. However, there was no evidence of an increased risk of autism if mothers received a diabetes diagnosis beyond their 26th week, or if they had type 2 diabetes prior to becoming pregnant. The study’s authors believe this is probably due to the women already having their blood sugar under control.
The study, which was published in the Journal of the American Medical Association, didn’t show why developing diabetes during pregnancy increased the risk of autism, although Anny Xiang, the study’s lead author, believes that it could be due to the long-lasting effects of high levels of blood sugar on the development of the foetus’ organs. These findings seem to confirm prior research which has suggested that the brain changes that cause autism happen a long time prior to delivery, with several studies also finding an increased risk of autism following the mother developing the flu during their pregnancy.
Paul Wang, head of medical research at Autism Speaks, says that autism appears to arise very early during the development of the brain. However he also says that having diabetes during pregnancy doesn’t necessarily mean that a child is likely to have autism, and that there are many reasons why children may develop this condition, including mothers not having enough folic acid during pregnancy. Other studies have also associated autism with the anti-seizure drug valporic acid, older mothers and fathers, and in children who are born prematurely or who have a very low birth weight.