Mothers who use antidepressants during pregnancy could double their children’s risk of develop autism.
The conclusions come from a new study covering 145,456 pregnancies.
Professor Anick Bérard of the University of Montreal, who led the study, said:
“The variety of causes of autism remain unclear, but studies have shown that both genetics and environment can play a role.
Our study has established that taking antidepressants during the second or third trimester of pregnancy almost doubles the risk that the child will be diagnosed with autism by age 7, especially if the mother takes selective serotonin reuptake inhibitors, often known by its acronym SSRIs.”
The Canadian researchers used data from the Quebec Pregnancy Cohort which followed 145,456 children until they were ten-years-old.
The results showed a number of factors that contributed to the risk of the child developing autism, including:
- Higher maternal age.
Each of these were taken into account but antidepressants still emerged as a risk factor, said Professor Bérard:
“We defined exposure to antidepressants as the mother having had one or more prescription for antidepressants filled during the second or third trimester of the pregnancy.
This period was chosen as the infant’s critical brain development occurs during this time.
Amongst all the children in the study, we then identified which children had been diagnosed with a form of autism by looking at hospital records indicating diagnosed childhood autism, atypical autism, Asperger’s syndrome, or a pervasive developmental disorder.
Finally, we looked for a statistical association between the two groups, and found a very significant one: an 87% increased risk.”
Since around 7% of pregnant women take antidepressants, the study could have very important implications.
Professor Bérard said:
“It is biologically plausible that anti-depressants are causing autism if used at the time of brain development in the womb, as serotonin is involved in numerous pre- and postnatal developmental processes, including cell division, the migration of neuros, cell differentiation and synaptogenesis — the creation of links between brain cells.
Some classes of anti-depressants work by inhibiting serotonin (SSRIs and some other antidepressant classes), which will have a negative impact on the ability of the brain to fully develop and adapt in-utero”
The study was published in the journal JAMA Pediatrics (Boukhris et al., 2015).
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