Breastfeeding increased infant survival rates in 19th -Century Montreal in two major ways, according to research from Concordia University and McGill University. Mother's milk protected vulnerable infants from food and water contaminated by fecal bacteria, while breastfeeding postponed the arrival of more siblings and that improved the health of mothers as well as their subsequent children.
Published in the journal Population Studies, using data gathered from Montreal's civil burial records and the 1881 Census, the study examined how poverty, poor sanitation, disease and various cultural factors affected death rates among newborns and children.
"Infant feeding practices, such as how long to breastfeed, at what age to introduce food supplements and in what season to wean, all influenced infant survival and all were subject to cultural tradition," says first author Patricia Thornton, a professor in the Concordia University Department of Geography, Planning and Environment.
Cultural groups that stopped breastfeeding earlier and especially before the summer when rising temperatures, dry weather and falling water table made contamination worst, were also more likely to have their next child more rapidly and less likely to limit their family size. This caused both the mother's and her next child's health to suffer.
"Poverty, high population density, room crowding and contagious diseases all affected death rates among children, yet these effects were nuanced by cultural identity," says co-author Sherry Olson, a professor in the McGill University Department of Geography.
The cultural factor
Studying 19th - Century health in Montreal was compelling for Thornton and Olson, since the city featured three well defined cultural groups: French Canadians, Irish Catholics and Protestants from Great Britain and Ireland. Each group had their own residential and occupational profile.
"Cultural factors eclipsed economic status as factors that influenced infant death rates," says Thornton. "Even though most French and Irish Catholics lived in similar working class conditions, the positive effects of later marriage and longer breastfeeding among Irish Catholics protected their infants and children, while French Canadians' infants were negatively impacted by early weaning."
According to the study, French Canadian women were weaning earlier, having more children and waiting less time between babies. What's more, French Canadian infants who survived their first year were more likely to suffer from bouts of intestinal diarrhea that could render them more vulnerable to common childhood illnesses.
Poverty and disease
Economic status, environmental conditions and neighbourhood characteristics all had an impact on newborns' and children's health and lifespan. High population density and crowded conditions helped the spread of contagious diseases and along with the presence of horses, and their impact on sanitation, all played a role in health, too.
"While French Canadian children bore a disproportionate share of urban deaths," says Thornton, "those who reached the age of 10 were as likely to survive as others and much more likely to survive than Irish Catholic men."
"The exceptional quality of records in Montreal provides a rare opportunity to study a North American metropolis in 1881, and to demonstrate the effects of poverty on infant and child mortality, as well as mortality over a lifetime," says Olson, noting, Montreal is one of few industrial cities where high-quality registration permits the examination of mortality with respect to a wide range of social and environmental factors.
"In the city of Montreal in 1881, the presence of three cultural communities from different economic backgrounds makes it possible to observe the way social settings affected survival over a lifetime," says Thornton.
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