Major Study looks at Association between Induced Labour and Autism
In a big study involving 600,000 births the odds of autism occurring increased by 23% in children whose mothers gave birth with induced or augmented labour according to Dr Simon Gregory and colleagues, as reported in the journal JAMA Pediatrics.
MedPageTodayreports; Induction only, augmentation only, or the combination all were associated with significantly increased odds of autism. The magnitude of increased risk was similar to that associated with fetal distress, meconium, prematurity, and maternal diabetes.
The authors of the report say, "Further investigation is needed to differentiate among potential explanations of the association including underlying pregnancy conditions requiring the eventual need to induce/augment, the events of labor and delivery associated with induction/augmentation, and the specific treatments and dosing used to induce/augment labor,"
The prevalence of autism in the US is about 1.1%. The cause of autism remains unknown, but most studies look at genetic predisposition as well as potential environmental factors.
The results of the study showed a consistent pattern of increased odds for autism among children whose mothers had induced or augmented labour:
Other factors that increased the odds for a diagnosis of autism included:
· Non-Hispanic black race/ethnicity,
· older maternal age,
· higher maternal education, and
· first born in birth.
Mode of delivery (vaginal versus cesarean) did not affect the odds.
The authors say that the results are not sufficient to suggest altering the standard of care regarding induction or augmentation; “Our results do suggest that additional research is warranted."
"We haven't established cause and effect," Gregory told MedPage Today. "We know that there are circumstances surrounding birth which have resulted in an elevated risk in autism, but we can't establish that it's the induction or augmentation process itself. It could be maternal health, it could be fetal health, or it could be the induction or augmentation process itself. We haven't made that link yet."
Dr Susan Hyman, MD, of the University of Rochester in New York told MedPage Today , "I would urge families to have open lines of communication with their healthcare provider so they can discuss indications for induction. However, the literature regarding the improvements in neonatal morbidity and mortality cannot be forgotten."
What is Autism?
Autism is part of a spectrum of disorders and is known as a ‘chronic neurodevelopmental disorder’. The symptoms, which normally show by the age of three include social and language impairments and characteristic repetitive patterns of behaviour. Other disorders within the spectrum include atypical autism, Asperger disorder, Rett disorder, childhood disintegrative disorder, and pervasive developmental disorder not otherwise specified. Autism was previously reported to affect approximately 5 of every 10 000 children,but prevalence rates of both autism and autism spectrum disorders (ASDs) may have increased markedly in the past decade.Recent studies conducted by the Centers for Disease Control and Prevention in the United States reported ASD prevalences of 3.4 and 6.7 per 1000 children. This increase may reflect a true increase in the incidence of ASD and implicates an important role of environmental causes.