Previously married mothers had higher rates of depressive disorders and alcohol abuse compared to married or never-married mothers, according to a new study from the Centre for Addiction and Mental Health (CAMH). The study, which highlights differing rates of psychiatric and substance use disorders between single and married mothers over a 12-month period, fills an important information gap in our understanding of the relationship between family structure and psychiatric outcomes.

Lead by Dr. John Cairney, Canada Research Chair, and Research Scientist in CAMH's Health Systems Research Consulting Unit, the study also showed that previously married mothers had higher rates of mental illness, when compared to currently married mothers. In addition, single mothers who were never married and married mothers have similar prevalence rates of psychiatric and substance use disorders. These rates were generally lower than the illness rates among women who experience a disruption in their marriage.

"This pattern of results suggests that divorced or separated women with children are at greater risk for psychiatric and substance use disorders," said Dr. Cairney.

Although the increased risk for psychiatric disorder among single mothers is well established, this study enhances our understanding by examining how the pathway to single-motherhood impacts mental health.

Added Dr. Cairney, "the picture of Canadian families has changed so dramatically over the past 60 years, including the dramatic rise in lone parent families. Understanding how these transformations in family structure influence health and well-being in our population is critical."

Dr. Cairney and his team suggest that clinicians look at the impact of marital history on the relationship between family structure and psychiatric outcomes, and carefully screen for psychiatric and substance use disorders in mothers who've experienced marital disruption.

For Dr. Lori Ross, Research Scientist in CAMH's Social Equity & Health Research Section, this study makes an important contribution by "enhancing our understanding of the relationship between single parenthood and mental illness, in particular by highlighting the diversity among single parents. The data show that it is important for both researchers and clinicians to recognize that all single parents are not alike. This concept is critical to understanding the context of single parenthood, its potential mental health implications."