New York, July 26 (IANS): A drug used by millions of people as the frontline treatment for Type-2 diabetes, may also play an unexpected role in blocking a significant cause of preterm birth, say researchers including one of Indian-origin.

"This proof-of-concept study illuminates a potential mechanism behind preterm birth," said senior author of the study Sudhansu K. Dey, Director of the Division of Reproductive Sciences at Cincinnati Children's Hospital Medical Center in Ohio, US.

"It also demonstrates possible remedies that are already approved for human use," Dey noted.

The early-stage study, based on results from mice bred to be prone to premature birth, was published online in JCI: The Journal of Clinical Investigation.

The study is important for two reasons, according to the researchers.

First, it details a little understood molecular pathway that can lead to premature birth by disrupting the function of the decidua - a thick membrane that lines the uterus and supports the continued growth of developing foetuses. 

Second, the researchers demonstrated - in mice -- two successful methods for restoring the lining's function and achieving healthy, full term births.

The study involved analysing mice bred to have a condition known to make pregnancies more likely to end in premature birth. 

The mice treated with metformin went on to have full term births, the findings showed.

The team also reported similar - but less effective - results when treating mice with resveratrol, an anti-oxidant and anti-aging dietary supplement made from grape seed extract.

In previous studies, Dey and colleagues discovered that rapamycin, an immune suppressing agent, showed promise in mice at preventing preterm birth. However, that medication may be risky for use in pregnant women.

Metformin appears to be a potentially safer alternative that works along the same molecular pathway, Dey said.

Preterm birth can be caused by many factors. It remains unclear how many preterm births are triggered by early decidual ageing, but Dey said it could be a significant number.

The process of preparing and conducting human clinical trials to further test the medications could take several years.