Stillbirth rates in First Nations and Inuit populations in Quebec are higher than in the general population, especially at term when most stillbirths are potentially preventable, researchers say.

Little is known about the timing and causes behind the higher rates of stillbirth among Inuit and First Nations populations compared with Canada's non-aboriginal populations. In Tuesday's issue of the Canadian Medical Association Journal, researchers in Quebec analyzed data on stillbirths and live births to try to find answers.

Improvements in pregnancy and obstetric care may be needed to close the gap in stillbirth rates. (Joshua Lott/Reuters)

"The gap widened at later gestational ages, and was largest at term, a period when most stillbirths are potentially preventable," Dr. Nathalie Auger of University of Montreal and her co-authors concluded.

In Inuit women, stillbirths were more likely to be caused by poor fetal growth, short gestation, and placental and related disorders, as well as birth defects that the researchers said may be linked to smoking.

For First Nations women, diabetes and complications of hypertension were considered the most important causes.

"Prevention may require improvements in pregnancy and obstetric care," the researchers said, suggesting anti-smoking and weight-reduction programs for women of reproductive age.

Rates of stillbirth were 6.8 per 1,000 total births for the Inuit women and 5.7 per 1,000 births for the First Nations women, compared with 3.6 per 1,000 for non-aboriginal women in Quebec.

During the study period of 1981 to 2009, 45 Inuit, 159 First Nations and 7,135 non-aboriginal stillbirths occurred at 24 or more weeks of gestation. The average human gestation is 40 weeks while before 37 weeks is considered pre-term.

Provincial stillbirth rates have fallen for Inuit and non-aboriginal populations but haven't improved for First Nations people. In Quebec, stillbirths need to be registered within eight days of delivery.

The researchers called for more efforts to record stillbirths at low gestational ages more completely.

The research was funded by Quebec's health research foundation.