In a recent CMAJ article, Gideon Koren and associates discuss maternal use of selective serotonin reuptake inhibitors (SSRIs) in the third trimester of pregnancy.1 Clinicians often speculate that a particular person with depressed mood has an abnormality of serotonin metabolism; however, life events, ingestion of toxins, abnormal biology and even poor diet or lack of exercise may be responsible for the depression instead. SSRIs and other antidepressant medications are often prescribed even though a specific test has not been done to confirm that the patient has abnormalities of serotonin levels or serotonin metabolism.
There is a dearth of strong evidence showing that antidepressant medications are substantially more effective than placebo or that the benefits of antidepressant medication outweigh the harms.2,3,4 We have not found any well-controlled studies showing that antidepressants reduce the risk of suicide in pregnancy, nor strong evidence that antidepressant medications are substantially more effective than placebo in reducing the pain of depression in pregnant women.
Koren is reported to have said, elsewhere, “What we found was that [among] pregnant women who use Paxil through pregnancy until birth, their offspring are more likely to have several stormy weeks at infancy.”5 In the absence of strong evidence that antidepressant medications are helpful, it seems reasonable to conclude that pregnant women and women of childbearing age, at least, should avoid taking antidepressants.