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Sarah McDonald

Sarah McDonald

Maternal & Child Obesity Prevention and Intervention
Canada Research Chair

Faculty of Health Sciences

Department of Obstetrics & Gynecology


Research Involves

Understanding, highlighting, and combating the risks of maternal and infant obesity.

Chair Overview

Half of all Canadian women of childbearing age are overweight or obese, and more than half gain too much weight during pregnancy. Both can lead to serious complications for themselves and their babies, including stillbirth.

For the baby, pre-pregnancy obesity increases the risk of premature birth; excess weight gain during pregnancy (PWG) is associated with high infant birth weight which in turn is associated with a doubling of the risk of obesity in childhood.

Sarah McDonald, an expert in perinatal research, is working to highlight the risks of maternal and infant obesity, understand who is most at risk, and develop interventions to promote healthy weight gain and, ultimately, improve the physical and mental well-being of women and their children.

A clinical epidemiologist and professor of obstetrics and gynecology, she led a meta-analysis of 84 studies involving more than one million women. It found overweight or obese women have a 30 percent greater risk of induced preterm birth before 37 weeks and that risk climbs to 70 percent for very obese women.

It was solid evidence of the seriousness of the relationship between obesity and pre-term birth, and now most obstetrical societies recognize these risks as well as the risks of excess weight gain during pregnancy.

McDonald’s findings pose serious public health implications for Canada and other countries in both the developed and developing world where maternal obesity rates are high. Prevention and early intervention is key. She is now seeking to identify new approaches to motivate mothers-to-be to have as healthy lives as possible during the important window on their infant’s health: pregnancy.