Simple treatment a breakthrough for millions with gestational diabetes

Researchers in Ireland have made a ‘significant step forward’ in the management of gestational diabetes, a condition that affects almost three million women worldwide every year.

The trial, carried out at the University of Galway, indicates that metformin, an existing and widely-used treatment for type 2 diabetes, is a safe and effective alternative for managing gestational diabetes mellitus.

Patients with the disorder typically have higher blood sugar levels during pregnancy. It has traditionally been managed through dietary advice and exercise, but where this is not successful, insulin is then introduced. 

However, this can lead to low sugars in both mother and baby, excess weight gain in mothers, higher caesarean rates and higher admissions into neonatal intensive care.

Mothers with gestational diabetes also face a greater risk of high blood pressure and preeclampsia.

The latest study involved 535 pregnant women, with 268 receiving metformin and 267 a placebo.

During the trial, 98% of women remained in the trial until delivery, with 88% completing the 12-week post-delivery follow up assessment – 4.9% of women discontinued the medication due to side effects.

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

The results also found that fasting and post-meal sugar values in the mother were significantly lower in the metformin group at weeks 32 and 38.

Delivery occurred at the same mean gestational age – 39.1 weeks – in both groups, and there was no evidence of any increase in preterm birth – defined as birth before 37 weeks – among those who received metformin.

Infants born to mothers who received metformin weighed, on average, 113g less at birth, with significantly fewer infants classified as large at birth, or weighing over 4kg.

There was a slight reduction in infant length – 0.7cm – but the study found no other significant differences in baby measurements.

The study also found no differences in adverse neonatal outcomes, including the need for intensive care treatment for newborns, respiratory support, jaundice, congenital anomalies, birth injuries or low sugar levels.

There were also no variations in rates of labour induction, caesarean delivery, maternal haemorrhage, infection or blood pressure issues during or after birth.

Fidelma Dunne, professor of medicine at University of Galway, will present the results at the 59th annual meeting of the European Association for the Study of Diabetes in Hamburg today.

‘While there is convincing evidence that improved sugar control is associated with improved pregnancy outcomes, there was uncertainty about the optimal management approach following a diagnosis of gestational diabetes,’ said Professor Dunne.

‘In our pursuit of a safe and effective treatment option, we explored an alternative approach – administering the drug metformin.

‘A previous trial compared metformin to insulin and found it to be effective, yet concerns remained, especially regarding preterm birth and infant size.’

Professor Dunne, who is also a consultant endocrinologist at Saolta University Health Care Group, said that babies born to mothers with gestational diabetes face their own set of risks, such as excessive weight at birth, birth injuries, respiratory difficulties and low sugar levels after delivery, potentially requiring admission to neonatal intensive care.

‘Gestational diabetes also increases the lifetime risk of diabetes for these mothers and their children,’ she said.

‘In addition, mothers have an elevated lifetime risk of cardiovascular disease. Furthermore, low and middle-income countries bear a significant burden of gestational diabetes cases.’

MORE : New diabetes drug that is ‘better’ than Ozempic and Wegovy set for use in UK

MORE : Zoo poo virus could save diabetes patients from limb amputations