Les experts contestent une nouvelle étude liant les naissances par césarienne à l'autisme

L'analyse, publiée dans JAMA Network Open, a examiné des études précédentes incluant des données de plus de 20 millions de naissances, constatant qu'il y avait un risque légèrement accru de développement chez un enfant autisme ou TDAH si elles étaient livrées par césarienne. The findings combined 61 studies from 19 countries dating back to 1999. However, the study did not suggest that caesarean deliveries cause autism or ADHD, only that there was an association.

The association found was very small. Children delivered by caesarean section were 1.33 times more likely to develop autism and 1.17 times more likely to develop ADHD. The risk of being diagnosed with autism or ADHD is already low, at around 1% and 7% for autism and ADHD respectively. This means that the risk of a child developing autism increases to around 1.33% if they are born via caesarean section rather than vaginally.

Both ADHD and autism are developmental disorders. Autistic spectrum conditions affect how someone communicates with and relates to other people. ADHD affects behaviour including concentration, hyperactivity and difficulty staying focused

The results and reporting of this meta-analysis are being contested by experts as an association between caesarean sections and developmental disorders does not mean that delivery by caesarean section causes ADHD and autism.

Il existe de nombreux facteurs qui augmentent les chances qu'une personne choisisse ou ait besoin d'une césarienne plutôt qu'un accouchement par voie vaginale. Les femmes qui sont obèse et plus âgés, ainsi que ceux qui ont des antécédents de conditions immunitaires telles que asthme, are more likely to have a caesarean section, says Andrew Whitehouse, Professor of Autism Research at the Telethon Kids Institute and the University of Western Australia.

"Tous ces facteurs ont également été associés à une probabilité accrue d'avoir un enfant autiste, et il est tout à fait possible - et certains diraient probable - qu'il soit plus probable que ces facteurs sous-tendent la relation entre la césarienne et les troubles neurodéveloppementaux," a-t-il déclaré dans un article pour The Conversation.

The researchers have said that more research is necessary in order to find the factors behind the association between caesarean sections and developmental disorders.

"This systematic review and meta-analysis shows an association between caesarean birth and autism and ADHD, but a number of underlying factors which may have led to the development of these conditions were not accounted for. Therefore, the findings of this paper do not show that caesarean birth leads to autism and ADHD," said Dr Pat O'Brien, Consultant Obstetrician and Spokesperson for the Royal College of Obstetricians and Gynaecologists.

"Women who have a caesarean birth should be reassured that it is a safe procedure. In many cases, a caesarean birth can be a lifesaving intervention, as well as the right choice for mother and baby. The vast majority of caesareans in the UK are performed for medical reasons, and should a woman request a caesarean, this should be fully supported in line with guidance from The National Institute for Health and Care Excellence."

Cette étude a été publiée dans JAMA Network Open.