Chen L, et al. - In this population-based linked birth cohort study, researchers ascertained if the impacts of pregestational diabetes mellitus (PGDM) and gestational diabetes mellitus (GDM) on perinatal and postneonatal mortality may differ in First Nations vs non-Indigenous populations. The study sample consisted of 17,090 First Nations and 217,760 non-Indigenous singleton births in 1996–2010, Quebec, Canada. In non-Indigenous but not First Nations infants, PGDM was related to an increased risk of postneonatal death. The associations were similar in adjustment to maternal and pregnancy characteristics. GDM was not linked in both groups to perinatal or postneonatal death. The investigation is the first to reveal that PGDM may increase the risk of perinatal death in First Nations vs non-Indigenous populations to a much greater extent, but only in non-Indigenous infants can significantly increase the risk of postneonatal death. The underlying causes are unclear and further studies are deserving. They speculate that differences in the population may be contributing factors in the quality of glycaemic control in diabetic pregnancies and/or genetic vulnerability to the fetal toxicity of hyperglycaemia.