Examining the effects of ambient temperature on preterm birth in Central Australia

Extreme hot and cold temperatures increase the risks of preterm birthThis study evaluated whether high ambient temperature increased the risk of preterm birth in Alice Springs, a remote town in Central Australia. Preterm birth is defined as birth before 37 completed weeks of gestation and is one of the leading causes of death among children under 5 years of age. Alice Springs has extreme heat conditions for more than three months of the year with temperatures reaching over 35 degrees Celsius (95 degrees Fahrenheit). Alice Springs also has more preterm births than the rest of Australia.

Data for this study included birth records obtained from the Department of Health. Of 16,870 single natural births that took place in Alice Springs Hospital (from 1986-2013), 1401 (8.3%) were preterm births. Additional data obtained from the Bureau of Meteorology focused on exposures to extreme temperatures during the last 3 weeks of pregnancy. Findings indicated that extreme hot and cold temperatures increased the risk of preterm birth for both Indigenous and non-Indigenous mothers. When the analysis was done with only the Indigenous women, daily maximum temperatures and age of mothers were significant variables. With non-Indigenous women, maximum temperatures, anemia, gestational diabetes and maternal age were all significant actors.

The results of this study are consistent with other research finding an association between temperature extremes (extremely hot and cold days) and preterm births. These findings are of particular relevance to health policy as Alice Springs is projected to become warmer as the climate changes. The projections of warmer temperature suggest that the risk of preterm birth will likely be higher in the future. Health practitioners, therefore, would do well to educate pregnant women about the need to decrease the amount of time they spend outdoors during the summer months. While this study focused only on Alice Springs, the need for similar precautions may be applicable to other hot desert locations around the world.