RESEARCHERS from the Queensland University of Technology have found a link between increases in temperature and the incidence of stillbirth and shorter pregnancies.
Associate Professor Adrian Barnett of QUT's Institute of Health and Biomedical Innovation led a study that looked at the incidence of still and premature births in Brisbane for four years from 2005.
Professor Barnett said 101,870 births had been recorded in the period and of these, 653 or 0.6% had been stillbirths.
"We found that increases in temperature increased the risk of stillbirth, and this was particularly true in the earlier stages of pregnancy before 28 weeks," he said.
"Our estimated numbers were there would be 353 stillbirths per 100,000 pregnancies at 15°C, compared with 610 stillbirths per 100,000 pregnancies at 23°C.
"Increased temperatures also shortened gestation times, which means more pre-term babies who often have serious long-term health problems."
Professor Barnett's study recorded weekly temperature, humidity and air pollution levels for each pregnancy.
He said the lowest risks had been in the coolest weeks, and that warm temperatures with weekly means of 23°C had been just as dangerous as the hottest weeks.
"This could be because most pregnant women would be more conscious of trying to remain cool on the hottest days and would generally seek air-conditioning," he said.
Professor Barnett said that as global temperatures rose, the study could have serious public health implications.
"Pregnant women should protect themselves from overheating to reduce the likelihood of pre-term or stillbirths," he said.