Depression
The months following childbirth are a time of heightened vulnerability to depressive mood changes.  Postpartum depression is defined in the Diagnostic and Statistical Manual of Mental Disorders,  Fourth Edition, (DSM-IV) ^40(p386) as a major depressive episode that occurs within 4 weeks of delivery. However, inconsistencies in the postpartum time frame (up to 6 months after delivery) make the literature on the epidemiology of postpartum depression difficult to interpret. Furthermore, reluctance on the part of women to endorse depressive symptoms at a time when they feel pressure to fit the stereotype of happy, fulfilled mothers may lead to reporting bias. 

Compared with depression occurring at other times in women’s lives, postpartum depression is frequently complicated by prominent anxious features. ⁴¹  Large and carefully controlled studies in the 6 to 12 weeks after delivery report rates of maternal depression at 12% to 16%. ^42–44

The overlap of depressive symptoms with those of normal childbirth sequelae can confound the clinical identification of postpartum depression. Changes in sleep, appetite, libido, fatigue, and worry are characteristic of both postpartum depression and a normal postpartum period.

Risk factors that help to identify postpartum mood disorder include prior episodes of postpartum depression, which is associated with a 50% to 62% risk of subsequent postpartum episode. ^45,46  Depressive symptomatology during pregnancy ^25,42,47  and family or personal history of major depression ^42,43,47 also appear to increase the risk for postpartum depression.

Marital discord, stressful life events, and ambivalence about the pregnancy are risk factors not only for depression during pregnancy but also for postpartum depression. ^{25,42,47–50}

Stressful newborn events, such as health problems and infant irritability, have also been associated with greater risk for postpartum depression. ^25,44,51 Two prospective cohorts ⁵² were analyzed to determine whether women who frequently brought their neonates for (problem-oriented) primary care or emergency department visits were at an elevated risk of having depressive symptoms.

  Findings revealed that neonatal health care use-patterns predicted maternal risk for postpartum depression;  mothers were more likely to have high levels of depressive symptoms if their infants had even 1 emergency department visit.

The father’s emotional state may also influence the risk for maternal postpartum mood changes. Depression ⁵³ and high levels of expressed emotion in a woman’s partner ⁵⁴ have been associated with greater likelihood of maternal depression in the 6 to 12 months after delivery. Finally, cultural factors may contribute to postpartum mood disturbances.

Attention to the new social role as a mother and social structuring of postpartum events plus assistance in the development of mothering skills have been suggested as possible factors that may protect against depressed mood after childbirth.⁵⁵