Postpartum depressive disorder is a spectrum of depressive disorders that typically includes postpartum blues, postpartum depression, and postpartum psychosis. Postpartum blues is by far the most common type, with an estimated prevalence ranging from 30% to 85%.[38,46] This relatively mild emotional disturbance is characterized by mild depressive symptoms such as mood liability, depression, irritability, tearfulness, generalized anxiety, increased sensitivity to criticism, fatigue, and disruptions in sleep and appetite.
These relatively benign and transient symptoms typically peak on the fourth or fifth day after delivery and remit by the tenth postpartum day. Although symptoms are time-limited and require little intervention, approximately 20% of women will develop MD in the first postpartum year. DSM-IV defines postpartum depression (PPD) as a major depressive episode that occurs within 4 weeks of delivery.
PPD is relatively common, with an estimated prevalence rate ranging from 10% to 16% during the 6 to 12 weeks after delivery.[38,45,47-49] Residual depressive symptoms may persist up to 1 to 2 years. These rates are very similar to the rates of depression observed in nonpuerperal women (that is, in women who have not just given birth). Because the symptom profile of PPD resembles that of a major depressive episode experienced at other times in life, the same DSM-IV criteria for MD apply to the diagnosis of PPD. The most reliable predictors of PPD are a prior history of MD (postpartum or nonpuerperal) and an absence of social support.
These two factors can double the risk of developing PPD. Prior PPD was associated with a 50% to 62% increased risk of subsequent postpartum episodes, and prior nonpuerperal MD was associated with a 30% risk of subsequent postpartum episodes.[45,47,48] Risk factors for PPD are shown in Table 6. Comorbid psychiatric illnesses, such as anxiety and obsessive compulsive disorder, are also prevalent in women with PPD.