Antidepressants Linked to Birth Defect
Study Shows Small Risk of Heart Defect From SSRIs Taken During Pregnancy
Sept. 24, 2009 -- New research adds to the evidence that babies born to
women who take antidepressants during pregnancy have a small increased risk for
a specific heart defect.
The Danish study also shows that the risk is greatest when moms-to-be take
more than one selective serotonin reuptake inhibitor (SSRI) antidepressant or
switch SSRIs early in pregnancy.
SSRIs such as Prozac, Paxil, Zoloft, Celexa and Lexapro are the most widely
prescribed drugs for depression; millions of women take them during
The new study shows the overall risk for congenital heart problems
associated with SSRI to be quite low.
But babies born to women who had filled prescriptions for more than one SSRI
had a fourfold increase in septal heart defects -- a malformation of the wall
that divides the left and right sides of the heart.
Unclear if All SSRIs Carry Risk
The finding will no doubt add to the confusion surrounding the safety of
specific SSRIs during pregnancy.
In 2005, based on the research at the time, the FDA singled out the drug
Paxil, warning that its use was associated with an increased risk for heart
It has since become common practice for doctors to switch women taking Paxil
to another SSRI when they become pregnant or are considering pregnancy.
But more recent studies suggest that women who take Paxil have no greater
risk for delivering babies with the heart defect than women who take other
In the Danish study, use of Celexa and Zoloft early in pregnancy was
associated with a small increased risk for the heart defect, but no association
was seen in women who took Paxil or Prozac.
The study compared the incidence of birth defects among babies born to
Danish women who did and did not take SSRIs during their first trimester. The
study included more than 400,000 children born between 1996 and 2003.
Septal heart defects occurred in 0.5% of children born to mothers who did
not take antidepressants and 0.9% of children born to mothers who did. SSRI use
was not linked to any other major birth defect.
"The bottom line is the risk associated with SSRI use appears to be very
small, and this has to be balanced against the very real risk associated with
having untreated depression during pregnancy," study researcher Lars H.
Pedersen of Aarhus University tells WebMD.
Larger Studies Needed
Pedersen says much larger studies are needed to determine whether any one
SSRI is safer or less safe than any other during pregnancy.
In an editorial published with the study Friday in BMJ Online First,
birth defects researcher Christina Chambers, PhD, agrees that larger studies
Chambers is an epidemiologist and associate professor at the University of
California, San Diego School of Medicine.