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. Depression is a common antenatal mental disorder associated with significant maternal morbidity and adverse fetal outcomes. However, there is a lack of research on the effectiveness or cost-effectiveness of psychological interventions for antenatal depression. A parallel-group, exploratory randomised controlled trial across five hospitals. The trial compared Guided Self-Help, modified for pregnancy, plus usual care with usual care alone for pregnant women meeting DSM-IV criteria for mild-moderate depression. The trial objectives were to establish recruitment/follow-up rates, compliance and acceptability, and to provide preliminary evidence of intervention efficacy and cost-effectiveness. The primary outcome of depressive symptoms was assessed by blinded researchers using the Edinburgh Postnatal Depression Scale at 14-weeks post-randomisation. 620 women were screened, 114 women were eligible and 53 (46.5%) were randomised. 26 women received Guided Self-Help – 18 (69%) attending ≥4 sessions - and 27 usual care; n = 3 women were lost to follow-up (follow-up rate for primary outcome 92%). Women receiving Guided Self-Help reported fewer depressive symptoms at follow-up than women receiving usual care (adjusted effect size −0.64 (95%CI: −1.30, 0.06) p = 0.07). There were no trial-related adverse events. The cost-effectiveness acceptability curve showed the probability of Guided Self-Help being cost-effective compared with usual care ranged from 10 to 50% with a willingness-to-pay range from £0 to £50,000. Despite intense efforts we did not meet our anticipated recruitment target. However, high levels of acceptability, a lack of adverse events and a trend towards improvements in symptoms of depression post-treatment indicates this intervention is suitable for talking therapy services.