This paper reviews the range of symptoms, timing and measurement of mood disturbance in the early puerperium. The prevalence and risk factors for postpartum blues and elation are discussed. The most convincing relationships are between blues and dysphoria during pregnancy, a past history of depression, neuroticism and premenstrual depression. Biological research is inconclusive. Blues and elation are predictors of subsequent postpartum depression and appear to be an index of affective vulnerability.