particularly when mental illness or a history of postpartum illness is found in first-degree relatives. Other biological factors examined for the part they play in the development of postpartum disorders include the effect of rapidly changing hormones and thyroid dysfunction following delivery.

The risk factors for development of postpartum disorders are many. Psychosocial risk factors include life stressors and sleep deprivation. Low economic status appears to be especially conducive to the development of postpartum depression while primiparity and a history of bipolar disorder are likely contributors to the onset of postpartum psychosis. The results of many family studies show a genetic link for the development of postpartum disorders