Maternal depression is a familiar plight around the globe — but its impact may be particularly acute in low-income nations. An analysis by epidemiologist Pamela Surkan, PhD, ScD, of Johns Hopkins Bloomberg School of Public Health, and psychologist Maureen Black, PhD, of the University of Maryland School of Medicine, and colleagues showed that maternal depression in developing countries was linked to growth problems in children (Bulletin of the World Health Organization, 2011).

The World Health Organization estimates the incidence of depressive symptoms among women in developing countries at anywhere from 15 percent to 57 percent — figures thought to be notably higher, Black says, than incidence of depressive mood in the United States. Childhood growth problems are also common in those countries, and several studies have found a link between growth and maternal depression.

To further investigate the connection, the researchers conducted a meta-analysis of 17 recent studies. They found that mothers with depressive symptoms were 40 percent more likely to have underweight or height-stunted children than mothers who were not depressed. Stunting under age 2 is important, Black says, because it's an indicator of chronic nutrition problems.

The concern extends beyond mere height. Children who are undernourished are at greater risk of low educational performance, reduced economic productivity and poorer health in adulthood.

Importantly, Black says, most of the studies she included in the analysis looked at depressive symptoms and depressive mood, not just clinically diagnosed depression. Since depressive symptoms are much more common than full-blown major depression, the ramifications for children's well-being could be far-reaching.

Most of the studies did not investigate the mechanism that underlies the connection between maternal depression and childhood stunting. The few that did suggested that depressive symptoms might negatively affect a mother's caregiving ability. "Mothers who are depressed are less responsive to their children and may have less energy to follow through with their children, so caregiving suffers," Black says.

Still, other mechanisms may be implicated as well. Depressed women may be less likely to breastfeed, for instance. And depression often goes hand-in-hand with factors such as poor family support and financial stress, both of which can undermine the health of a child. "It's likely that there's more than one mechanism," Black says.

More research is needed to flesh out the details, says Surkan. But in the meantime, she adds, there are plenty of other reasons to address maternal depression. "Even if confirmatory research still needs to be done, I don't think it would be too soon to say that we should do something about maternal depressive symptoms, both for the mothers and the children."

The authors report that some low-cost approaches, including social support, group therapy and home visits by lay community workers, have been shown to ease depressive symptoms among women in developing nations. But establishing affordable, effective interventions will require a multidisciplinary approach that draws on psychologists, nutritionists and public health experts, Black says. "This is an illustration of how psychology can work with broad health issues," she says.

—K. Weir