Using antidepressants during pregnancy greatly increases the risk of the child later developing autism, according to new research.

The University of Montreal study reviewed data from 145,456 pregnancies between the time of their conception up to age ten, in addition to information about the mother's use of antidepressants and the child's eventual diagnosis of autism.

“A new study has indicated that using antidepressants during pregnancy greatly increases the risk of autism in the child.“

It was revealed that taking antidepressants during the second or third trimester of pregnancy increased the risk that the child would be diagnosed with autism by age seven by 87 percent, especially if the mother takes selective serotonin reuptake inhibitors (SSRIs).

These are extremely significant findings, as six to ten percent of pregnant women are currently being treated for depression with antidepressants.

Study leader Professor Anick Berard of the University of Montreal said: "Our work contributes to a better understanding of the long-term neurodevelopmental effects of antidepressants on children when they are used during gestation. Uncovering the outcomes of these drugs is a public health priority."

The prevalence of autism among children has increased from four in 10,000 children in 1966 to 100 in 10,000 today, leading to concerns that environmental factors may be responsible for this trend.