Evidence continues to mount that use of antidepressants in pregnancy increases the risk of autism spectrum disorder in offspring. Specifically, the class of antidepressants with autism risk are selective serotonin reuptake inhibitors (SSRIs). SSRIs include Prozac, Paxil, Lexapro, and Zoloft. The latest study to report the association was published online on December 14 in the journal JAMA Pediatrics by Canadian researchers.
The authors note that the association between the use of antidepressants during pregnancy and the risk of autism spectrum disorder in children remains controversial. They explain that the etiology (underlying causes) of autism spectrum disorder are unclear; however, studies have implicated genetic factors, environmental risk factors, and maternal depression. Therefore, the objective of the study was to assess the risk of autism spectrum disorder in children associated with antidepressant use during pregnancy according to trimester of exposure and taking into consideration maternal depression. (Pregnancies are often categorized into three month periods, or trimesters)/
For the study, the researchers reviewed data from the ongoing study, the Québec Pregnancy/Children Cohort, which includes data on all pregnancies and children in Québec from January 1, 1998, through December 31, 2009. A total of 145,456 singleton (single pregnancy) full-term infants born alive and whose mothers were covered by the Régie de l’assurance maladie du Québec drug plan for at least 12 months before and during pregnancy were included. The data were analyzed from October 1, 2014 through June 30, 2015.
Antidepressant exposure during pregnancy was defined according to trimester and specific types of antidepressants. Children with autism spectrum disorder were defined as those with at least one diagnosis of the disorder between date of birth and last date of follow-up. The data were subjected to statistical analysis to estimate risk.
The investigators found that during 904,035.50 person-years of follow-up, 1,054 children (0.7%) were diagnosed with autism spectrum disorder; boys with the disorder outnumbered girls by a ratio of approximately 4:1. The average age of children at the conclusion of follow-up was 6.24 years. Adjusting for potential confounders (factors that could skew the data), use of antidepressants during the second and/or third trimester was associated with the risk of autism spectrum disorder (31 exposed infants; 1.87-fold increased risk). Use of SSRIs during the second and/or third trimester was significantly associated with an increased risk of ASD (22 exposed infants; 2.17-fold increased risk). The risk was persistent even after taking into account maternal history of depression (29 exposed infants; 1.75-fold increased risk).
The authors concluded that the use of antidepressants, specifically SSRIs, during the second and/or third trimester increases the risk of ASD in children, even after considering maternal depression. They recommended that further research should be conducted to specifically assess the risk of autism spectrum disorder with antidepressant types and dosages during pregnancy.
The researchers are affiliated with: Faculty of Pharmacy, University of Montréal, Montréal, Québec, Canada; Research Unit on Medications and Pregnancy, Research Center, CHU Sainte-Justine, Montréal, Québec, Canada; Centre d’excellence en Troubles Envahissants du Développement de l’Université de Montréal, Montréal, Québec, Canada; Département de Psychiatrie, Hôpital Rivière-des-Prairies, Montréal, Québec, Canada; Centre de Recherche de l’Institut Universitaire de Psychiatrie de l’Université de Montréal, Montréal, Québec, Canada; and Department of Pharmaceutical Sciences, University of Montréal, Montréal, Québec, Canada.