A first-of-its-kind international study led by Western Sydney University has shown that treatment of gestational diabetes from early pregnancy adds additional protection for babies and mothers from pregnancy complications.

Published in the New England Journal of Medicine, the new research explored whether treatment of gestational diabetes before 20 weeks' gestation among those already at high risk improves maternal and infant health, finding a reduction in complications.

Through a randomized controlled trial performed at 17 hospitals in Australia, Austria, Sweden and India, the study screened more than 43,000 women to recruit 802 women with a diabetes risk factor before 20 weeks' gestation, who had gestational diabetes by the World Health Organization definition.

Lead author Distinguished Professor David Simmons from the University's School of Medicine and Translational Health Research Institute said the study provides new evidence for those deemed at higher risk for early testing and treatment of gestational diabetes beyond the current recommended approach of intervening at 24–28 weeks.

"Testing for gestational diabetes is offered routinely later in pregnancy and those at higher risk are also tested early on to exclude undiagnosed type 2 diabetes. If these early glucose values are increased, but below those diagnostic of type 2 diabetes, we feel we should treat but data has been lacking to demonstrate the effects of such treatment on the mother or baby; we have now filled this major knowledge gap likely affecting millions of pregnancies every year," said Distinguished Professor Simmons.

The study assessed pregnancy outcomes with the initiation of treatment for gestational diabetes before 20 weeks, compared with no early treatment and subsequent initiation of treatment depending on results of repeat oral glucose tolerance testing (OGTT) at 24–28 weeks' gestation, with significant and unexpected findings relating to respiratory distress in babies.

"Over one in twenty babies avoided a group of severe birth complications including birth damage like broken bones or nerves, or getting stuck during birth known as shoulder dystocia. In addition, breathing problems requiring oxygen were almost halved and the number of days needed in neonatal intensive care or special care unit were down by 40%," explained Distinguished Professor Simmons. "Furthermore, severe damage to and around the mother's birth canal, known as perineal injury, was reduced by over three quarters."

The research team recommends further confirmatory trials and long-term follow-up studies of offspring. Professor Simmons said, "In the meantime, it's really important that we now use these new findings to review the existing guidelines for gestational diabetes, agree on the best cut-offs for its diagnosis and start protecting mothers and babies as soon as we can."