A recent study shows that an increasing number of mothers are developing postpartum depression, but the incidence of depression among women of reproductive age has also increased over time. A researcher says that the incidence of postpartum depression has especially increased among first-time mothers and older mothers, which may help to identify specific risk groups.
Postpartum depression is more in focus than ever. The difficulty parents face and how this affects their mental health was less prominently recognised previously.
A recent study shows that an increasing number of mothers have developed postpartum depression over the past 20 years.
The study also shows an overall increase in the incidence of depression among women of reproductive age, but for postpartum depression, the incidence has especially increased in certain groups of women.
According to a researcher behind the study, this could call for increased awareness and identification in specific groups.
“The fact that specific groups account for the overall increase in the number of mothers who develop postpartum depression is surprising. We need to be aware of this situation and examine more closely why they develop postpartum depression and what can be done to prevent it or offer support during a vulnerable time,” explains Sofie Dyekær Egsgaard, PhD Fellow, Research Unit of Child and Adolescent Psychiatry, Department of Clinical Research, University of Southern Denmark, Odense.
The research has been published in the Journal of Affective Disorders.
Study covered women giving birth in Denmark in the past 20 years
Sofie Dyekær Egsgaard and colleagues used Denmark’s national health registries to identify women diagnosed with depression between 2000 and 2022.
Women diagnosed with depression within six months of giving birth were characterised as having postpartum depression.
The study also used data on redeemed antidepressant prescriptions as a marker for depression or postpartum depression.
The researchers sampled a background population by matching five women for each delivery on the date of childbirth to compare trends in postpartum depression and to depression among women of reproductive age in general.
The data showed increases in the incidence of both postpartum depression and depression among women of reproductive age.
The study included 1,133,947 postpartum women (669,101 unique mothers) matched to 5,669,735 women from the background population (1,165,505 unique women).
Notable increase in postpartum depression
The results indicate that the incidence of women with postpartum depression and depression has increased since 2000.
For example, 27.3 mothers per 10,000 person-years had postpartum depression in 2000 compared with 42.7 in 2022.
In the background population, 13.3 women per 10,000 person-years were diagnosed with depression in 2000 compared with 22.9 in 2022.
“The incidence of both postpartum depression and depression among women of reproductive age has increased over time. The incidence of postpartum depression is overall higher than the incidence of depression during the entire period, as was to be expected,” says Sofie Dyekær Egsgaard.
Specific groups account for the increase
The observed increase in postpartum depression could be related to a general increase in the incidence of depression among women of reproductive age, but the situation is more complex.
The researchers divided their analyses based on maternal age and whether they were first-time mothers or had one or more children. When they did this, they found that the increase in depression incidence among all women of reproductive age was largely driven by an increase among younger women.
Conversely, the researchers found that the increase in postpartum depression over time was more pronounced among older mothers compared with younger mothers.
Similarly, the researchers also found that postpartum depression predominantly increased among first-time mothers and not among mothers who had already given birth to one or more children.
“Since this was a descriptive study, we cannot explain the reasons behind our findings. We can only observe that the numbers indicate that older mothers and first-time mothers seem to have increased vulnerability to postpartum depression over time,” explains Sofie Dyekær Egsgaard.
Probably only the tip of the iceberg
Sofie Dyekær Egsgaard believes that the study could generate hypotheses for further research to examine more closely why these two groups of mothers seem to be especially vulnerable after giving birth.
Further studies might also indicate why the proportion of women who develop postpartum depression has increased over 20 years.
Is facing motherhood more challenging today than it was previously, or is women’s mental health not as robust as it used to be?
“We should recognise that the incidence of postpartum depression is increasing and strive to identify new mothers who are struggling, especially since more mothers are affected today. Becoming a mother is a life-changing event, and we therefore need to help mothers who are having difficulties in this situation,” says Sofie Dyekær Egsgaard.
She elaborates that these results are probably only the tip of the iceberg, since the researchers only have data from women who have sought and received help for their mental health issues in psychiatric care or who received medication to treat postpartum depression or depression.
“Many women experience postpartum depression that does not lead to specialised psychiatric care or medication. Mothers with postpartum depression who are treated within the municipal system do not appear in the health registries, and we therefore expect the true number of women with postpartum depression to be higher than what we observed in our study,” concludes Sofie Dyekær Egsgaard.
