New research suggests the stress associated with postnatal depression influences future fertility levels.
A team of evolutionary anthropologists at the University of Kent discovered women with postnatal depression are unlikely to have more than two children.
Their findings have been published in the journal Evolution, Medicine and Public Health.
Researchers note that until now, very little has been known about how women’s future fertility is impacted by the experience of postnatal depression.
Investigators collected data on the complete reproductive histories of over 300 women to measure the effect postnatal depression had on their decision to have more children.
The mothers were all born in the early to mid-20th century and the majority were based in industrialized countries while raising their children.
The research team concluded that postnatal depression, particularly when the first child is born, leads to lowered fertility levels.
Experiencing higher levels of emotional distress in her first postnatal period decreased a woman’s likelihood of having a third child, though did not affect whether she had a second.
Furthermore, postnatal depression after both the first and the second child dissuaded women from having a third child to the same extent as if they had experienced major birth complications.
Investigators Sarah Myers, Drs. Oskar Burger and Sarah Johns said this is the first research to highlight the potential role postnatal depression has on population aging.
They believe the finding is especially important as the median age of a country becomes older over time. This demographic change is mostly caused by women having fewer children, and can have significant social and economic consequences.
Given that postnatal depression has a prevalence rate of around 13 percent in industrialized countries, with emotional distress occurring in up to 63 percent of mothers with infants, the need for improved maternal health is important both for the health of the mother and the nation.
As such, investing in screening and preventative measures to ensure good maternal mental health now, may reduce costs and problems associated with an aging population at a later stage.