Are antidepressants associated with heart defects in pregnancies?

This paper studied the effects of antidepressant use during pregnancy on heart defects.

Antidepressant medications are used to treat depression. More and more people are using antidepressants during pregnancy. Selective serotonin-reuptake inhibitors (Celexa, Lexapro) are the most commonly prescribed antidepressants during pregnancy. Currently debates exist about whether antidepressants increase the risk of congenital cardiac malformations (heart defects present from birth). 

949,504 complete pregnancies in women were studied. Mothers who took antidepressants in their first trimester (the first three months of pregnancy) were identified. The types of drugs studied were selective serotonin reuptake inhibitors , tricyclic antidepressants (Norpramin, Tofranil), serotonin norepinephrine reuptake inhibitors (Cymbalta, Effexor XR), bupropion (Wellbutrin), paroxetine(Pexeva), sertraline (Zoloft) and others.

In the first trimester, 6.8% of women used an antidepressant. Women who took antidepressants were older and used more health care. 

Upon taking into account many factors that could affect results (for example an actual diagnosis of depression) the risk of cardiac malformation was found. The risk was 6% higher among women who took selective serotonin reuptake inhibitors and 20% higher in serotonin norepinephrine reuptake inhibitors.The risk was 23% lesser with tricyclic antidepressants and 8% lesser with bupropion. 

There was no significant result regarding dosage of antidepressants.

The authors concluded that the use of antidepressants during the first trimester does not significantly increase the risk of certain cardiac defects.

The study classified women who took antidepressants based on their prescription history, which may not guarantee women actually took antidepressants.