Galway researchers make breakthrough on gestational diabetes treatment

Condition affects almost 3 million pregnant women worlwide every year

Researchers at University of Galway have made a significant advance in the safe treatment of gestational diabetes, a condition that affects up to 7,000 expecting mothers each year.

Metformin, a medicine used to lower body sugar levels, can be an effective option for managing gestational diabetes, researchers at the university have established.

More than 500 pregnant women participated in the randomised, placebo-controlled trial of the early use of metformin, which was managed by the Galway researchers.

Gestational diabetes affects almost 3 million pregnant women worldwide every year. It is characterised by elevated blood sugar levels during pregnancy, posing increased health risks for mothers and their babies.


Doctors already knew that improved sugar control among affected women was associated with improved outcomes from pregnancy. However, there was uncertainty about the best way to manage pregnancies after gestational diabetes was diagnosed.

The trial found that women assigned to metformin were 25 per cent less likely to need insulin, and when insulin was necessary, it was started later in the pregnancy.

Women receiving metformin had lower sugar levels and gained less weight than the control group, the trial found. On average, they delivered at the same time, about 39 weeks. There was no evidence of any increase in preterm birth or higher caesarean rate.

The children born to the women weighed on average 113 grams less than the control group. There was a slight reduction in their length but no other significant differences in measurements, and there was no different in adverse outcomes after birth.

“The results from the study are a significant step forward for women with gestational diabetes,” according to endocrinologist, Prof Fidelma Dunne. “Metformin has emerged as an effective alternative for managing gestational diabetes, offering new hope for expectant mothers and healthcare providers worldwide.”

Traditionally, gestational diabetes has been managed through dietary advice and exercise, with insulin introduced if sugar levels remain sub-optimal. “While effective in reducing poor pregnancy outcomes, insulin use is associated with challenges, including low sugars in both the mother and infant which may require neonatal intensive care, excess weight gain for mothers, and higher caesarean birth rates,” Prof Dunne points out.

The study is being published on Tuesday in the Journal of American Medical Association to coincide with the presentation of the trial results by Prof Dunne at a meeting of the European Association for the Study of Diabetes in Hamburg.

Paul Cullen

Paul Cullen

Paul Cullen is Health Editor of The Irish Times