Finding an alternative to metformin for gestational diabetes: The GUARD trial

Diabetes that is diagnosed during pregnancy is often treated with metformin, but the drug isn’t always effective. Our researchers have set up a trial to test whether a different drug might be more effective at preventing health complications for mother and baby.

  • Authors list

    Professor Catherine Williamson, Professor Helen Murphy, Dr Caroline Ovadia, Dr Alice Mitchell, Dr Peter Dixon, Holly Lovell

    Start date: 2020
    End date: 2022

This project took place at our London centre which operated between 1995 and 2021.

Why do we need this research?

Diabetes diagnosed in pregnancy – known as gestational diabetes – affects around 35,000 women in the UK every year. These women are more likely to experience pregnancy complications such as pre-eclampsia, premature birth and stillbirth, and there is also an increased risk of their children having obesity, cardiovascular disease or type 2 diabetes in later life. Metformin is a drug that is often used to treat gestational diabetes, but it isn’t always effective. We urgently need to find new ways of treating gestational diabetes to help reduce the risks for babies.

What’s happening in this project?

Ursodeoxycholic acid (or UDCA for short) is a drug that is currently used to treat another pregnancy complication called​​​​​​​ intrahepatic cholestasis in pregnancy. Researchers supported by Tommy’s have carried out some work that has suggested that UDCA might also be a useful treatment for gestational diabetes, and they want to look into this further. As UDCA works in a different way to metformin, it is possible that it may be a better option for controlling gestational diabetes, reducing the chances of complications for both mother and baby.

Our researchers are now setting up the GUARD trial to find out whether UDCA is more effective than metformin at treating women with gestational diabetes. In the trial, women will be given either UDCA or metformin to treat their condition. The team will compare how well the two drugs are able to control blood glucose levels and will also find out whether treatment with UDCA improves outcomes for babies.

As well as this trial, our researchers will carry out work in the lab to find out more about how UDCA and metformin work.

What difference will this project make?

This study will find out if UDCA is better than metformin at treating diabetes during pregnancy. If successful, this would give doctors a new treatment that can be used to reduce the risks of the condition for both mother and baby.

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