MONDAY, July 4, 2011 (Health.com) — Children whose mothers take Zoloft, Prozac, or similar antidepressants during pregnancy are twice as likely as other children to be diagnosed with autism or a related disorder, according to a small new study, the first to examine the relationship between antidepressants and autism risk.
This class of antidepressants, known as selective serotonin reuptake inhibitors (SSRIs), may be especially risky early on in a pregnancy, the study suggests. Children who were exposed to the drugs during the first trimester were nearly four times as likely to develop an autism spectrum disorder (ASD) compared to unexposed children, according to the study, which appears in the Archives of General Psychiatry.
The study included fewer than 300 children with a diagnosed ASD and does not prove that taking SSRIs during pregnancy directly causes ASDs, which affect approximately 1% of children in the U.S. The findings will need to be confirmed in larger studies, and should not dissuade women from starting or continuing to take SSRIs, experts on prenatal drug exposure and mental health say.
“Poor maternal mental health during pregnancy is a major public health issue,” says Tim Oberlander, MD, a professor of developmental pediatrics at the University of British Columbia, in Vancouver. “Nontreatment is not an option. While some children might be at risk from an SSRI exposure—and we don’t know who, and how that works—there are many mothers and their children as well who will benefit.”
The lead author of the study, Lisa Croen, PhD, the director of autism research at Kaiser Permanente Northern California, a large nonprofit health plan based in Oakland, emphasizes the preliminary nature of her team’s findings. “This is the first study of its kind to look at the association, and the findings have to be interpreted with a lot of caution,” she says. “We can’t detect causality from one study.”
Untreated depression during pregnancy carries its own risks, such as preterm birth and growth problems, Croen adds, and “the potential risks to the child really have to be balanced with the risk to the untreated mom. We don’t want people to rush off and stop taking antidepressants if they’re on them. They really need to talk to their doctors about the risk-benefit ratio.”
Max Wiznitzer, MD, a pediatric neurologist at Rainbow Babies & Children’s Hospital and an associate professor of pediatric neurology at Case Western Reserve University School of Medicine, both in Cleveland, says the study is too small to draw any conclusions. The study is a “signal,” he says, “but with a really small group.”
Using Kaiser Permanente’s patient database, which includes more than 3.2 million people, Croen and her team identified 298 children with an ASD who were born between 1995 and mid-1999, and matched them with 1,507 children without autism who were roughly the same age and were born in the same hospitals.
The authors then cross-checked whether their mothers, in the year before delivery, filled prescriptions for an SSRI, including Prozac, Zoloft, Luvox, Celexa, and Paxil (or their generic versions). The researchers could not confirm whether the mothers actually took the medication, however.