An exploratory parallel-group randomised controlled trial of antenatal Guided Self-Help (plus usual care) versus usual care alone for pregnant women with depression: DAWN trial.

•This study is one of the first RCTs to assess the efficacy of a CBT-based antenatal Guided Self-Help intervention for pregnant women diagnosed with depression.•This RCT found that Guided Self-Help can be successfully delivered to depressed women in early pregnancy.•This antenatal Guided Self-Help intervention signalled improvements in women's depressive symptoms post-treatment.•The findings of this RCT suggest that an antenatal Guided Self-Help is suitable for use in talking therapy services.