Postpartum depression and anxiety distinct from other mood disorders, at least in brain scans

Postpartum depression is considered much like any other form of depression: New mothers withdraw from family and friends, lose their appetites, and feel sad and irritable much of the time.

A new paper contends there is uniqueness of mood and emotional disorders that arise during pregnancy or shortly after giving birth. It uses fMRI, which has not been shown to be valid for diagnosis, but may provide some insight into what's happening.

Overall, fMRI studies show that neural activity in women with postpartum depression compared to people with major depression who had not given birth involves distinct patterns for new mothers with postpartum depression. For instance, the amygdala is usually hyperactive in anxious and depressed people, but for the women with postpartum depression, the amygdala can actually be less activated. That shows that problem with fMRI.

Postpartum depression  is now listed as "perinatal depression," a subset of major depression, in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the text which acts as a glossary for the industry. Postpartum anxiety isn't included at all in the DSM-5, even though 1 in 7 new mothers claim to have it, says psychologist Jodi Pawluski of University of Rennes. On surveys, postpartum anxiety is estimated to be just as prevalent as postpartum depression, but it hasn't been taken seriously enough as a distinct condition to get much attention in the literature. Many of these mothers aren't depressed, so their condition remains largely unaddressed.

Postpartum mood disorders not only affect mothers but also their infants. New mothers experiencing postpartum anxiety or depression are more likely to snap at their infants and may have trouble forming a bond. Those early interactions can have a long-term impact on infants' health, psychologists believe. The experience of postpartum depression can be further complicated by the fact that women are expected to enthusiastically embrace their new motherhood. Many women with postpartum mood disorders don't feel that they can discuss the issues and feelings they're having openly.

Still, if it affects nearly 1 in 10 women,  Pawluskibelieves postpartum depression and postpartum anxiety should not be treated as extensions of major depression and generalized anxiety disorder, respectively.