Is autism linked to premature birth

Antidepressants in Pregnancy - Increased Risk of Autism

Montreal (Canada) - Taking an antidepressant in the last six months of pregnancy is associated with an approximately two-fold increased risk of autism for the child. This is what Canadian doctors report in the journal "JAMA Pediatrics". Your study does not show a causal relationship. However, the results strongly suggest that the drugs could interfere with normal brain development in the unborn child. On the one hand, there was no such connection if the antidepressants were taken before the beginning or in the first trimester of pregnancy - the critical phase of brain development does not begin until after the third month of pregnancy. On the other hand, this relationship was particularly pronounced for one drug group - the so-called selective serotonin reuptake inhibitors (SSRIs). Therefore, the result cannot simply be traced back to common genetic causes of depression and autism.

"It would be biologically plausible that antidepressants from the group of selective serotonin reuptake inhibitors cause autism if they are used in the child's brain development phase," says Anick Bérard of the University of Montreal. "Because serotonin is involved in numerous development processes, including the formation of synapses, the connection points between brain cells." Selective serotonin reuptake inhibitors are among the most commonly prescribed drugs for depression. They block the resumption of the messenger substance serotonin released by nerve cells at the synapses, which increases the concentration of this neurotransmitter.

Bérard and her colleagues evaluated data from 145,456 children born between 1998 and 2009 in the province of Quebec after a normal gestation period. Of these, 0.7 percent developed an autistic disorder within an observation period of an average of six years after birth. Four times more boys than girls were affected. About 4,700 women had taken at least one drug for depression during pregnancy. If the time of taking the medication was in the second or third trimester of pregnancy, the risk of autism for the child increased by 87 percent compared to the untreated women. Taking antidepressants in the first three months of pregnancy or the year before did not affect the risk of illness. For those treated with SSRIs in the last two trimesters of pregnancy, the risk increased by more than one hundred percent. In the statistical analysis, the age of the women was taken into account and whether there was a previous burden of depression in the family. Data on the dosage of the drugs taken were not available.

It is a difficult trade-off between benefits and risks when it comes to deciding whether or not pregnant women should be treated with antidepressants for depression, writes Bryan King of Seattle Children's Hospital in an accompanying comment. It is well known that untreated depression would increase the likelihood of premature birth and mental disorders in the child. Therefore, further studies are now necessary that compare the effects of different drugs and take different dosages into account.

Early childhood autism is a developmental disorder that has both genetic and environmental causes. The disease leads to impaired perception and information processing, which affects communication and social behavior. Asperger's syndrome is a mild form of autistic disease.

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