A new study published December 14 in JAMA Pediatrics revealed a startling link between antidepressant use during pregnancy and autism. Women who took a class of antidepressants known as selective serotonin reuptake inhibitors (SSRI)—which includes Zoloft, Prozac and Paxil—during the second and third trimester had more than double the risk of having a child with autism. The study authors conclude that those children were 87 percent more likely to be diagnosed on the autism spectrum.
The study followed more than 145,000 Canadians from conception to 10 years of age. Some 4,700 of those children were exposed to antidepressants at some point in utero and among those children, 46 of them developed autism. The study also found that women who took more than one class of antidepressants while pregnant had more than four times the risk of having a child with autism compared to women who took no antidepressants.
Lead researcher Anick Bérard tells The Independent, "It is biologically plausible that antidepressants 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 neurons, cell differentiation and synaptogenesis—the creation of links between brain cells."
It has long been suspected that there's a strong connection between a mother's history of depression and an increased likelihood of autism in her children, but this is the first study to whittle it down to a specific class of antidepressants and specific trimesters during gestation.
Many women battle depression while pregnant, and now doctors are worried that the findings of the study will be overblown and prevent expecting mothers who really do need assistance managing their depression from seeking help.
Bryan King, a program director of the autism center at Seattle Children's Hospital, claims in an editorial that was published with the study that "this study doesn't answer the question [of what causes autism]. My biggest concern is that it will be overinterpreted."
And he's not wrong.
A previous study, released earlier this year, found there was no strong link between antidepressants and autism; a 2013 Danish study concluded the same thing. And while the 87 percent figure sounds scary, when you take into account that the risk of having a child with autism as a whole is only 1 percent, it puts things into less panicky perspective.
Granted, there is also a 2013 study out of Sweden that did find a connection, but it's hard to know what the actual link is—the depression or the antidepressants. Generally women with more severe depression will have to stay on antidepressants longer, well into the second and third trimester, so it's impossible to determine which is the actual risk factor.