Antidepressant Use in Pregnancy Tied to Autism Risk
But the risk is low, and it's important to treat depression in pregnant women, experts say
By Serena Gordon
MONDAY, April 14, 2014 (HealthDay News) -- Boys with autism were three times more likely to have been exposed to antidepressants known as SSRIs in the womb than typically developing children, according to new research.
The new study also found that boys whose mothers took SSRIs -- drugs including Celexa, Lexapro, Paxil, Prozac and Zoloft -- during pregnancy were also more likely to have developmental delays.
Results of the study were published online April 14 and in the May print issue of Pediatrics.
"We found prenatal SSRI exposure was almost three times as likely in boys with autism spectrum disorders relative to typical development, with the greatest risk when exposure is during the first trimester," said study co-author Li-Ching Lee, an associate scientist in the department of epidemiology at Johns Hopkins Bloomberg School of Public Health, in Baltimore.
While the study found an association between prenatal use of SSRI antidepressants and autism risk in boys, it did not prove cause-and-effect.
The study authors were quick to point out that there are risks to both the mother and fetus from untreated depression.
"It's a complex decision whether to treat or not treat depression with medications during pregnancy," Lee said. "There are so many factors to consider. We didn't intend for our study to be used as a basis for clinical treatment decisions. Women should talk with their doctors about SSRI treatments."
Other experts said the overall risk of having a child with autism remains very low.
SSRIs used during pregnancy cross the placenta and increase levels of the hormone serotonin in the fetus, as they do in the mother, the researchers said. Higher serotonin levels decrease depression, and these antidepressants are used in about 4 percent of all pregnancies, according to background information with the study.
About one in three children with autism has higher-than-normal serotonin levels. Researchers think these high levels may lead to the development of abnormal brain circuitry, which may play a role in the development of some autism symptoms, according to the study authors.
The new study is the latest in an ongoing debate about SSRI use during pregnancy and its possible association to autism spectrum disorders. Other studies on SSRI use in pregnancy have produced conflicting findings.
One study published in the November 2011 Archives of General Psychiatry that included nearly 300 children with autism spectrum disorders found double the risk of autism when the mother had used SSRIs, with a stronger link to SSRI use during the first trimester.
Another study, published in the Dec. 19, 2013 New England Journal of Medicine, included almost 4,000 children with autism spectrum disorders. This study didn't find a significant association between autism and SSRI exposure during pregnancy.