Phototherapy study sheds light on depression in pregnancy

Phototherapy may alleviate depressive symptoms in pregnant women, providing a potential alternative to antidepressants, a small Swiss study suggests.

Researchers at the Psychiatric Hospitals of the University of Basel, Switzerland, randomly assigned 46 depressed pregnant women to 5 weeks of treatment with either a bright fluorescent light or a nontherapeutic dim red light (19 women discontinued treatment during the study or started taking antidepressants). Investigators instructed the women to sit under the light for 1 hour each day within minutes of waking. The women met weekly with researchers who evaluated their depression using the 29-item Structured Interview Guide for the Hamilton Depression Rating Scale with Atypical Depression Supplement.

After 5 weeks, more women in the light therapy group (13 of 16) showed at least a 50% improvement in symptoms compared with the placebo group (5 of 11); 11 were no longer depressed, compared with 4 in the placebo group.

“The study provides evidence that light therapy, a simple, cost-effective antidepressant modality with minimal side effects for the mother and no known risk for the unborn child, may be a useful nonpharmacologic approach in this difficult situation,” the authors write. They note that approximately 10% of pregnant women are depressed, which increases the risk of preterm delivery and a low birth weight baby.

The response in the study to light therapy was equivalent to the response produced by antidepressant drugs on pathways in the brain, says lead author Anna Wirz-Justice, PhD. Concern about the potential impact of antidepressants on the fetus has led to reluctance to prescribe the drugs for pregnant women.

Women may benefit from more than 5 weeks of light therapy, perhaps throughout pregnancy and postpartum, Wirz-Justice says. Further studies are under way to confirm the efficacy of phototherapy in pregnancy.

The study was published online April 5 in the Journal of Clinical Psychiatry.