Is birthweight an appropriate health-outcome measure for Torres Strait Islander babies?

Background: Although Torres Strait Islanders (TSls) are often combined with Aborigines, they are a distinct group and would prefer to be considered se parately. The Queensland Perinatal Data Collection (QPDC) has been the only population-based, perinatal collection in Australia that has distinguished between Aboriginal and TSI mothers. It provided a unique opportunity to co mpare outcome measures based on birthweight in the TSI, Aboriginal and whit e populations. TSls were of particular Interest because recent research fro m overseas suggests that in groups with high rates of obesity and diabetes, birthweight is not a valid outcome measure,This is of concern because outc ome measures based on birthweight have been proposed as a way of monitoring the neonatal health of Indigenous Australians. Methods: Retrospective analysis of 10 years of routine data from the QPDC. Results: TSls had a birthweight distribution similar to that of whites, but mortality rates similar to those of Aborigines. For birthweights between 2 500g and 4000g, TSls had mortality rates that were 2.5 times higher than th ose for whites (95% CI: 1.3 to 4.2). Conclusions: Although birthweight is widely used, it is not necessarily a v alid outcome measure in all populations. For TSls, maternal conditions such as obesity and diabetes might cause changes in the uterine environment tha t produce heavier, but not healthier babies.