NEW YORK (Reuters Health) – The results of a large population-based study in Denmark suggest that children born to women who use selective serotonin reuptake inhibitors (SSRIs) in early pregnancy are at increased risk for septal heart defects. Still, the authors emphasize that the absolute risks are low.
The risk is most pronounced with sertraline and citalopram or when more than one type of SSRI is used, according to the report in the September 25th Online First issue of BMJ.
Although prior reports have tied SSRIs with heart defects, they have also linked the drugs to certain major malformations, such as omphalocele and craniosynostosis. The present findings, however, indicate no association with major malformations, lead author Dr. Lars Henning Pedersen, from Aarhus University, Denmark, and colleagues note.
The new study involved 493,113 children born from 1996 to 2003 and followed through December 2005. Data from registers on filled prescriptions, deliveries, and hospital diagnoses were used to assess SSRI use and malformation occurrence.
Overall, SSRI use in early pregnancy, defined as 28 days before to 112 days after the start of gestation, was associated with a near twofold increased risk of septal heart defects.
Sertraline carried the highest risk, with an odds ratio of 3.25, followed by citalopram (2.52), and fluoxetine (1.34). Use of more than one SSRI was associated with an odds ratio of 4.70.
“We were surprised by the higher prevalence of septal heart malformations among children of mothers that changed or used more than one SSRI during early pregnancy. Interpreted in the context of previous studies, this may suggest a class effect of the SSRIs,” Dr. Pedersen told Reuters Health.
As noted, the absolute risk of septal heart defects was low. The prevalence in unexposed children was 0.5% versus 0.9% and 2.1% in children exposed to any SSRI or more than one SSRI, respectively.
“Future studies,” Dr. Pedersen noted, “could address the potential associations with more rare malformations, include data on the underlying depression, or investigate potential associations between SSRIs and other outcome, including a potential effect on brain development. We have studies underway that focus on all these aspects.”
In an accompanying editorial, Dr. Christina Chambers, from the University of California, San Diego, comments that “although research about SSRIs and pregnancy outcomes is plentiful, it does not necessarily provide definitive answers for clinical practice. Clinicians and patients need to balance the small risks associated with SSRIs against those associated with undertreatment or no treatment.”
