Fewer Canadian infants die before their first birthday compared with the Americans, but Canada ranked behind most European countries on the health-care indicator in a new report.

Canada ranked 25th out of 31 countries in the world in infant mortality, researchers from the U.S. National Center for Health Statistics found.

The infant mortality rate is the number of infant deaths that occur before a child's first birthday per 1,000 live births.

In 2005, the latest year that international rankings were available, Canada ranked 25th in the world, behind Singapore, Australia, New Zealand, Hong Kong, Spain, Japan and Israel, the report's authors said.

Infant mortality rates are considered a key indicator of the overall quality of a country's health-care system.

Higher native infant mortality rate

In March, researchers found the infant mortality rate for native babies in Canada, the U.S., Australia and New Zealand is four times that of non-native newborns.

In Canada specifically, the infant mortality rate for children on reserves was twice that of non-natives, the study found. Inuit babies are four times more likely to die.

Social deprivation factors such as low household income, poor water quality, substandard housing and lack of access to health care, rather than genetics, were some of the reasons researchers pointed to the disparity.

Last month, a report by the March of Dimes found more than 10 per cent of births in North America, or 500,000 babies, are preterm, up 36 per cent since the mid 1980s. Africa had the most preterm births at 12 per cent.

The largest proportion of the increasing preterm birth rate in North America is a result of late preterm births — babies born after 34 weeks of gestation. The WHO defines normal term delivery as between 37 weeks and 42 weeks.

In North America, the benefits of medical advances and better general health have been offset by the rising number of women over age 35 having babies, and the increasing use of assisted reproductive technologies that are more likely to result in preterm births.