The purpose of this multicentre and quasi-experimental study is to evaluate the effect of a web-based course for community nurses in Iceland with regard to outcome of postpartum emotional distress. A sample of six community health centres was selected and equally divided into an experimental and a control group. All nurses at the experimental centres attended a web-based course focusing on evidence-based interventions for postpartum emotional distress. All new mothers were screened 9 weeks postpartum using the Edinburgh Postpartum Depression Scale (EPDS). If they scored 12 points or more they were eligible for the study. Mothers answered the EPDS at three different points in time, (9, 15 and 24 weeks postpartum) and the Parent Stress Index: Short Form (PSI/SF) at two times (9 and 15 weeks). Results showed no significant difference in the rate of depressive symptoms between study centres at 9 weeks. At 15 and 24 weeks there was, however, a significant difference between mothers at the experimental and control centres. Nurses at the experimental centres documented significantly more evidence-based interventions than did nurses at the control centres, and they had more frequent contact with new mothers suffering from postpartum emotional distress. There was no significant variation in PSI scores between the groups at any time. More women at the experimental centres were on antidepressants compared to the control centres. Of the total of 32 women eligible for the study, 10 declined participation. The findings are limited by small sample size and a probable confounding effect of antidepressants with the nursing interventions. Findings indicate that the web-based transfer of knowledge to nurses on evidence-based interventions for postpartum emotional distress has a positive effect on distressed women in the postpartum period and warrants further study.