Postpartum psychosis, a more severe form of postpartum mood disorder, occurs in about 1 to 2 per 1,000 women following childbirth. Postpartum psychosis is one of the leading causes of the murder of children less than one year of age, which occurs in about 8 per 100,000 births in the United States. Signs and symptoms
Symptoms of PPD can occur any time in the first year postpartum. Typically, a diagnosis of postpartum depression is considered after signs and symptoms persist for at least two weeks. Emotional
Persistent sadness, anxiousness or "empty" mood
Severe mood swings
Frustration, irritability, restlessness, anger
Feelings of hopelessness or helplessness
Guilt, shame, worthlessness
Low self-esteem
Numbness, emptiness
Exhaustion
Inability to be comforted
Trouble bonding with the baby
Feeling inadequate in taking care of the baby
Thoughts of self-harm or suicide

Behavioral
Lack of interest or pleasure in usual activities
Low libido
Changes in appetite
Fatigue, decreased energy and motivation
Poor self-care
Social withdrawal
Insomnia or excessive sleep
Worry about harming self, baby, or partner

Neurobiology
fMRI studies indicate differences in brain activity between mothers with postpartum depression and those without. Mothers diagnosed with PPD tend to have less activity in the left frontal lobe and increased activity in the right frontal lobe when compared with healthy controls. They also exhibit decreased connectivity between vital brain structures,  including the anterior cingulate cortex, dorsal lateral prefrontal cortex, amygdala, and hippocampus. Brain activation differences between depressed and nondepressed mothers is more pronounced when stimulated by non-infant emotional cues. Depressed mothers show greater neural activity in the right amygdala toward non-infant emotional cues as well as reduced connectivity between the amygdala and right insular cortex.
Support groups and group therapy options focused on psychoeducation around postpartum depression have been shown to enhance the understanding of postpartum symptoms and often assist in finding further treatment options. Other forms of therapy, such as group therapy, home visits, counseling, and ensuring greater sleep for the mother may also have a benefit. While specialists trained in providing counseling interventions often serve this population in need, results from a recent systematic review and meta-analysis found that nonspecialist providers, including lay counselors, nurses, midwives, and teachers without formal training in counseling interventions, often provide effective services related to perinatal depression and anxiety.Internet-based cognitive behavioral therapy (iCBT) has shown promising results with lower negative parenting behavior scores and lower rates of anxiety, stress, and depression. iCBT may be beneficial for mothers who have limitations in accessing in person CBT. However, the long term benefits have not been determined. Medication
A 2010 review found few studies of medications for treating PPD noting small sample sizes and generally weak evidence. Some evidence suggests that mothers with PPD will respond similarly to people with major depressive disorder. There is low-certainty evidence which suggests that selective serotonin reuptake inhibitors (SSRIs) are effective treatment for PPD. The first-line anti-depressant medication of choice is sertraline, an SSRI, as very little of it passes into the breast milk and, as a result, to the child. However, a recent study has found that adding sertraline to psychotherapy does not appear to confer any additional benefit.