Women in large urban areas at higher risk of postpartum depression

Women living in large urban centres in Canada with more than 500 000 inhabitants were at higher risk of postpartum depression than women in other areas, according to a study in CMAJ (Canadian Medical Association Journal).

Postpartum depression is a serious health concern for women and their children around the world. Major risk factors include lack of social support and a history of depression. In Canada, about 20% of people live in rural or remote regions, 35% live in the large urban areas of Montréal, Toronto and Vancouver, with the remaining 45% in semirural or semiurban areas, but the effect of urbanicity on postpartum depression is not known.

To understand the influence of place of residence on postpartum depression, researchers looked at data for 6421 women living in rural, semirural, semiurban or urban areas who participated in the 2006 Canadian Maternity Experiences Survey. Rural was defined as people living in settlements smaller than 1000 people or with 400 or more inhabitants per square kilometer; semirural (under 30 000), semiurban (30,000-499,999) and urban (500 000 and over). The researchers also factored in the effect of whether residents commute to larger urban centres because this can affect the degree of social isolation.

The prevalence of postpartum depression in the sample group was 7.5%. Women in urban areas were at higher risk, with almost 10% reporting postpartum depression compared with 6% of women in rural areas, almost 7% of women in semirural areas and about 5% in semiurban areas. Urban areas had higher numbers of immigrant populations, and more women in these areas reported lower levels of social support during and after pregnancy.

"We found that Canadian women who lived in large urban areas…were at higher risk of postpartum depression than women living in other areas," writes Dr. Simone Vigod, psychiatrist at Women's College Hospital and scientist at Women's College Research Institute, Toronto, with coauthors. "The risk factors for postpartum depression (including history of depression, social support and immigration status) that were unequally distributed across geographic regions accounted for most of the variance in the rates of postpartum depression."

"Supports and services targeted toward increasing connections for isolated women in large urban centres may need to be increased in Canada," conclude the authors. "Considering the substantial negative effect of postpartum depression, such interventions could have broad-reaching social and public health impact."