Many mothers experience symptoms of depression after giving birth. A new review showed that the severity and length of postpartum depression varied widely between women.
This review examined previous studies on the course of postpartum depression.
The researchers found that postpartum depression can last for a year or more for many women. Additionally, long lasting postpartum depression could be a precursor for other mental health problems.
Some studies also showed that certain risk factors, like a lack of partner support, can increase a woman's risk of developing postpartum depression.
Sara Casalin, PhD, of the Department of Psychology in the University of Leuven, led the review on postpartum depression.
Postpartum depression is a type of depression that affects women who have recently given birth. Women with postpartum depression may experience sadness, anxiety, irritability and feelings of low self-esteem.
Postpartum depression usually begins around one month after birth and often lasts for several months.
This review looked at previous studies on postpartum depression published from 1985 to 2012 to investigate the course of postpartum depression and recovery. Each of these studies involved long-term follow-up visits.
The researchers identified 23 studies that dealt with length postpartum depression and the intensity of symptoms over time.
Seven studies followed up with women after one to 3.5 years. They each showed a significant decrease in depression between the initial assessment and the follow-up visit. These studies suggested that the severity of postpartum depression may decrease over time.
One prominent study found that the majority of postpartum depressive episodes went away after three to six months. Six other studies found that about 35.5 percent of women still had depression three to four months after giving birth.
The researchers also reviewed 12 studies examining subgroups of women with postpartum depression.
Those studies all consistently identified a group of women who were chronically depressed, meaning that their postpartum depression did not go away after a year or more.
The authors of this review suggested that many mothers may experience a decline in symptoms, then a less severe relapse (return of symptoms).
This review also looked at factors that influenced the course of postpartum depression.
Nine studies looked at the impact of the the mother's age. Two studies concluded that depressed mothers tended to be slightly younger, but the other seven found no age-related influence on postpartum depression.
Socioeconomic status was examined in nine studies. Two studies found that chronically depressed women had lower education levels and income. Six studies found no socioeconomic influence.
Three studies found that women who were less satisfied with their partner relationship and support had a higher risk of postpartum depression.
Parental stress was cited as a risk factor for postpartum depression in two studies, and financial worries increased the risk in three studies.
The authors of this review concluded that women with postpartum depression generally experienced a lessening of symptoms, although many remained depressed.
Additionally, an estimated 30 percent of women may continue to experience symptoms throughout their child's first year of life.
The researchers noted that lasting postpartum depression could lead to chronic depression and other mental health problems. They also noted that certain risk factors, like poorer partner relationships and a history of depression, could intensify a woman's risk for postpartum depression.
These researchers recommended that more research be done to address the different courses of postpartum depression.
This review was published in the January/February issue of the Harvard Review of Psychiatry.
The researchers did not disclose funding sources and reported no conflicts of interest.