directory-466935_1280For all of the awareness that has been generated about postpartum depression, there is a great deal that is still unknown about the disorder. Is postpartum depression a unique type of depression where women experiencing it are biologically different than those experiencing a major depressive episode at another point in life? Or is postpartum depression a major depressive episode that occurs in a specific timeframe? What about depression that begins during pregnancy? Is it wholly and distinctly different than depression that sets in six weeks after birth? Believe it or not, even the diagnosis of postpartum depression is technically unofficial.

Walker Karraa, Ph.D., author of Transformed by Postpartum Depression: Women’s Stories of Trauma and Growth, explains how The Diagnostic and Statistical Manual of Mental Disorders (DSM), fifth edition and the International Statistical Classification of Diseases and Related Health Problems, tenth edition address, or rather do not address, postpartum depression, saying,

“Unfortunately there is not official diagnostic criteria for any perinatal mood or anxiety disorder in either the DSM5 or the ICD-10. With postpartum depression for example, the DSM categorizes it as an episode of Major Depressive Disorder that has an onset specifier of occurring within 4-6 weeks after childbirth.”

However, a new study published in the January edition of The Lancet Psychiatry provides important new insight on postpartum depression. Researchers at the University of North Carolina School of Medicine evaluated data on over 10,000 women diagnosed with postpartum depression in an attempt to answer some of the above questions.

The study focused on women who were diagnosed as having major depression within 12 weeks of giving birth to a single live fetus and were without history of schizophrenia, biopolar disorder or psychotic symptoms. The data reviewed was provided from researchers in seven countries through the Postpartum Depression: Action Towards Causes and Treatment (PACT), a psychiatry consortium created in 2010 to support research on the causes of postpartum depression.

The research team at the UNC School of Medicine did a statistical analysis of the data, including symptom ratings from the Edinburgh Postnatal Depression Scale or the Hamilton Depression Rating Scale (it varied depending on what scale had been administered to the patient), when symptoms began, pregnancy and obstetrical complications, previous history of depression or anxiety and suicidal ideation.

After analyzing this data, three specific classes of postpartum depression emerged based on severity of symptoms. Referred to simply as Class 1, 2 and 3 in the study, the creation of tiered classes could help bring greater clarity to the disorder and help providers assess and manage risk factors for their patients, leading to better treatment and outcomes.

When evaluating these three classes, researchers found some interesting commonalities among those who experienced the most severe levels of postpartum depression. Sixty-seven percent of women with the most severe symptoms (class 3 as identified in this study) reported that their symptoms began during pregnancy. This group was also more likely to have a history of mood disorders. The researchers conclude that for these women, it may be that postpartum depression is part of a larger pattern of depression or anxiety rather than a specific response to the hormonal changes associated with birth. Interestingly, women assigned to class 3 based on symptom severity were more likely to have experienced obstetrical complications. This may indicate that obstetrical complications may be a potential trigger for depression or anxiety, particularly in women with a prior history of these disorders. The DONA Doula Chronicles previously shared a study that evaluated the connection between pain during childbirth and increased risk of postpartum depression (Do Epidurals Reduce the Risk of Postpartum Depression?).

“What is so powerful about the PACT study is that they are asking women about the experience; having women inform science about the disorder is critical to clarifying current nosology.” — Walker Karaa, Ph.D.

More research, such as this most recent study from the University of North Carolina, is needed to determine whether there are certain types of depression and anxiety during pregnancy and postpartum. This determination could have significant impact on how women are evaluated for risk of developing a mood disorder in pregnancy or postpartum, the prevention of severe symptoms including suicidal thoughts and the best course of treatment for each woman.

‘Heterogeneity Of Postpartum Depression: A Latent Class Analysis’. The Lancet Psychiatry 2.1 (2015): 59-67. Web.

Additional information can be found about this study: