A sweeping new review shines a light on this subset of women, finding that while symptoms of postpartum depression generally diminish with time, an estimated 30 to 50 percent of moms affected with the disorder continue to struggle with major depression throughout the first year after birth -- and beyond. The review, its authors argue, highlights the need for clinicians to view women with postpartum depression, or PPD, as a highly heterogeneous group, and to understand that for many, there is no clear beginning or end.
"In some mothers ... depressive symptoms indeed decrease over time after childbirth, consistent with the assumption of many researchers in the field that a majority of depressive episodes after childbirth resolve within three to six months," said Sara Casalin, a researcher with the University of Leuven in Belgium and an author on the study, in an email to The Huffington Post. "However ... in a substantial proportion of mothers with PPD, levels of depression do not always significantly decrease, and particularly do not decrease to normal levels."
Recent estimates suggest that as many as 1 in 7 women battle postpartum depression for reasons that are not entirely known. PPD differs from the so-called "baby blues" -- postpartum sadness, exhaustion and mood swings that are common among many women -- both in terms of severity and timing. Baby blues generally lasts for only a few weeks after birth, while experts generally agree that postpartum depression can occur anytime within the first year.
The new review, published in the January/February issue of the Harvard Review of Psychiatry, considered 23 studies on postpartum depression conducted between 1985 and 2012. It found that for 38 percent of women with PPD, the disorder is the "prelude to the development of a chronic depressive disorder," or may be the continuation of a pre-existing problem or vulnerability.
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