Study: Immigrants living less than five years in Canada less likely to have premature babies

Policies to ensure immigrants are not trapped in poor neighborhoods could have positive health impacts

Immigrants living less than five years in Canada are less likely than their Canadian-born counterparts to have premature babies regardless of where they live, according to a new study by St. Michael's Hospital.

"Living in poor neighbourhoods has been linked with poor health outcomes, but this study shows that this is not always the case for new Canadians," says Dr. Marcelo Urquia, epidemiologist at the Centre for Research on Inner City Health at St. Michael's Hospital. "For new immigrants, while they have an advantage on avoiding premature births in the early years, they progressively lose it and actually experience an accelerated deterioration when living in deprived urban areas. We need to take steps to make sure new Canadians can find upward socioeconomic mobility when they arrive."

Previous studies have shown that the longer immigrants stay in Ontario cities, the higher the risk of premature delivery. This study extends these findings and uncovers new data including:

• Once immigrants have lived in Canada for 15 years or more, they have higher premature birth rates than Canadian-born residents living in the poorest neighbourhoods.
• While the risk of premature delivery increases for most immigrants with time spent in Ontario cities, those who live in poor neighbourhoods experience the highest risk.

"For the first 15 years in Canada, the study found that the maternal country of birth was a better indicator of the risk of premature birth," says Dr. Urquia. "After that period, the pattern is reversed and immigrants reach the level of inequalities in premature birth observed at the neighbourhood level among Canadian-born residents."

Published in the Journal of Urban Health, the study reviewed birth data from Ontario hospital records from 2002-2007 and were linked to an official Canadian immigration database for 1985 to 2000.

A premature birth involves a baby born that is less than 37 weeks of gestational age and is at much greater risk of short and long term complications including disabilities and impediments in growth and mental development.