A comprehensive review of clinical studies examining postpartum depression carried out in January 2014 has shown that although symptoms of postpartum depression in most women recede over time, for a large number of women, depression remains a long-term problem.
Although it is common to experience mood swings or become tearful in the weeks following childbirth, in some women these symptoms may become more persistent and severe, and could be an indication of postpartum depression.
We already know that postpartum depression usually occurs in the first 4 to 6 weeks after giving birth, and it is unlikely to get better by itself.
This makes recognizing the symptoms of postpartum depression very important, so that doctors are able to provide the appropriate treatment without impacting the care of the baby.
In this report, published in the Harvard Review of Psychiatry, researchers compared the findings of studies on postpartum depression published between 1985 and 2012. The researchers wanted to identify risk factors that make some women more prone to persistent postpartum depression.
They also wanted to see what limitations the existing studies into postpartum depression may have, and what implications this has had for women with postpartum depression and their children.
Although all follow-up studies examined in the review found that symptoms of postpartum depression decreased over time, the scores grading symptoms did not fall beneath the cut-off point for clinical depression for many women. Overall, the review found that 38% of women with postpartum depression experienced chronic symptoms.
In women who were receiving medical care, 50% of patients experienced depression for more than 1 year after childbirth. The review also found that in women who were not receiving clinical treatment, 30% of women with postpartum depression were still depressed up to 3 years after giving birth.
What factors increase the risk for chronic depression?
Some of the studies believed that women suffering from chronic postpartum depression were most likely experiencing a continuation of pre-existing depression, rather than a new set of symptoms arising from giving birth.
The review found the strongest evidence that poor partner relationships, stress and a pre-existing history of depression and sexual abuse made women more likely to experience chronic depression after giving birth.
Some studies that the review drew its evidence from also suggested that young mothers, mothers on a low income, and mothers from a minority background were more likely to develop chronic postpartum depression, but the data was less consistent for these findings.
Illnesses in the child did not seem to increase the likelihood of the mother developing long-term depression.
Areas for further study
The review did not find much information on how effective treatments were for long-term postpartum depression. Also, the definition of postpartum depression was not standardized across all of the studies that the review looked at.
So the researchers believe that further, larger studies are needed that use a standard definition of the illness and consistent follow-up methods.
The authors of the review believe that the findings of their work emphasize a need for doctors to be aware of potential signs of postpartum depression becoming chronic when treating patients, and that taking into account wider contributing factors to depression is key to this.
The research team also acknowledged that more educated management of the condition should limit the adverse effects on child development, saying that:
"Because postpartum depression (PPD) has significant consequences for the baby, for the depressed mother, and for the early relationship between mother and child, knowledge about prolonged changes in the mental health of mothers with PPD may not only improve our understanding of the course of PPD, but also inform prevention and intervention strategies."