A pioneering research program aiming to optimize steroid use in pregnancy, and minimize potential side effects of excess steroid exposure to both mother and baby, is set to benefit the millions of families worldwide who will have babies born too soon.

The long-standing collaborative Western Australian-based program, involving researchers from the Women and Infants Research Foundation, Cincinnati Children's Hospital, USA, and Tohoku University Hospital, Japan, has sought to investigate the importance of duration and magnitude of steroids exposure to mature the lungs of preterm infants.

Findings published this week in the prestigious medical journal, The American Journal of Obstetrics & Gynecology, have shown that in preterm lambs, high peak drug exposures do not contribute to the effectiveness of antenatal steroids. Rather, the duration of low-concentration steroid exposure is key for preterm lung maturation.

Chief Investigator at the University of Western Australia, Associate Professor Matt Kemp, said the findings represent a major breakthrough in the field of obstetrics.

"The use of steroid therapy in pregnancy to rapidly mature the fetal lung, making breathing easier and safer for preterm babies, has been responsible for saving the lives of countless thousands of preterm babies."