New Study Supports Cardiac Safety of SSRIs in Pregnancy
Concerns about the safety of psychiatric medications during pregnancy are common among psychiatrists and patients alike. In many cases, one must weigh the risks of a medication to mother or child against the risks inherent in untreated mental illness. Recent research, however, lends support to the growing data about the safety of antidepressant medications in pregnancy.
In a study conducted between 2000 and 2007, researchers examined medical records of close to a million pregnant women in 46 U.S. states and evaluated cardiac outcomes of their liveborn infants. A total of 64,389 women in the study sample used antidepressants during the first trimester. From these women, 580 infants (90.1 per 10,000) were born with a cardiac defect, as compared to 6,403 (72.3 per 10,000) born to women who had not taken antidepressants. The relative risk of any cardiac defects with the use of SSRIs in the first trimester was 1.25 (95% CI, 1.13 to 1.38).
While this suggests an elevated risk, the researchers pointed out that antidepressants are prescribed for other conditions (pain disorders, fatigue, smoking, etc). When they adjusted the analysis for women with a diagnosis of depression and for other confounding variables such as known or suspected risk factors for heart defects, the relative risk was reduced to 1.06 (95% CI, 0.93 to 1.22)—a non-significant elevation.
Researchers did not find a doseresponse relationship either in terms of when the medication was started (looking back as far as three months before the first missed menstrual period) or in terms of the highest dose dispensed. Interestingly, they found no significant association between two anticipated risks, namely, paroxetine and right ventricular outflow tract obstruction (RR 1.07, 95% CI, 0.59 to 1.93) or sertraline and ventricular septal defects (RR 1.04, 95% CI, 0.76 to 1.41) (Huybrechts KF et al, NEJM 2014;370:2397–2407).
TCPR’s Take: Past epidemiologic studies have shown an association between first-trimester antidepressant use and congenital cardiac defects, but this study found that the risk of cardiac malformations was no higher for depressed women who took SSRIs (or other antidepressants) than for those who did not, after controlling for other potential risk factors. Limitations of the study include the use of prescription records, which do not indicate whether women actually took the medication; and the exclusion of miscarriages, stillbirths, or termination of pregnancy, all of which may be a consequence of fetal cardiac malformation.