This article presents an overview of research on postnatal depression conducted with postnatal women only. Research spanning three areas is reviewed, namely, prevalence, mothers' experiences and treatments. The review shows prevalence rates varying from 4.4% to 73.7%, with the most recent systematic review suggesting a rate of 13%, indicating a serious clinical issue for nurses providing postnatal care to mothers. Mothers' experiences of living with postnatal depression exemplify such feelings as loneliness, anxiety, hopelessness, and loss of control at a time when expectations of joyousness are anticipated. Results of research on treatment options show limited success with antidepressant medications, some success with psychotherapeutic options, and the importance of social support for mothers with postnatal depression. Comparisons of studies are made from methodological perspectives, drawing on their strengths and limitations. Overall, this review highlights the high prevalence rates of postnatal depression, negative feelings exemplified by mothers' living with this condition, and the limited success of treatment options available to mothers. Postnatal depression is a significant clinical issue for nurses providing postnatal care for mothers and is underassessed, misunderstood, and very often poorly treated. (c) 2007 Elsevier Inc. All rights reserved..