The CONCEPTT study: using continuous glucose monitors to improve outcomes in pregnant women with type 1 diabetes

In a large, international study, our researchers have shown that continuous glucose monitors help pregnant women with type 1 diabetes to better control their glucose levels

This study is now complete

Type 1 diabetes is becoming more common and so it is crucial that we understand how best to help pregnant women who have the disease. It can be hard to manage type 1 diabetes in pregnancy – blood glucose levels can be erratic and there can be severe consequences for both mother and baby if diabetes is poorly controlled.

Around 1 in 2 babies have complications that are linked to their mother having high glucose levels during pregnancy, with 50% being born too large, 40% being delivered prematurely and 40% being admitted to a Neonatal Intensive Care Unit.

We recently completed this CONCEPTT study, which looked at whether the use of continuous glucose monitors could improve glucose control and infant outcomes in women with type 1 diabetes who were pregnant or planning a pregnancy.

What are continuous glucose monitors?


Continuous glucose monitors give women real-time information about their blood glucose levels, allowing them to make more informed choices about the amount of insulin they need.

Comparing it with other methods

This international study included 325 women from 31 hospitals – the women used either continuous glucose monitoring or standard home glucose monitoring.

We found that blood glucose levels were within a healthy range considerably more often – approximately 100 minutes a day – when women used a continuous glucose monitor instead of a standard home monitor.

This seems to have had a positive effect on infant outcomes, as fewer babies born to this group of women were large for their gestational age or needed to be admitted to a Neonatal Intensive Care Unit for more than 24 hours.

NICE are reviewing their guidelines after this trial

These results are important as they show that continuous glucose monitoring helps pregnant women control their type 1 diabetes and so improve outcomes for their babies. As a result, NICE are formally reviewing their guidelines for the use of continuous glucose monitors in pregnant women with type 1 diabetes, meaning that our study could have national implications.


Join the fight for healthy pregnancies and babies

Tommy's funds research across the UK investigating the reasons for miscarriage, stillbirth and premature birth, and fighting to make pregnancy and birth safer. We can keep you updated on ways you can support our work. If you would like to join our fight, click here.

More about Tommy's research

  • Three pregnant women sitting in a row

    Research into health and wellbeing in pregnancy

    In addition to our core work on miscarriage, stillbirth, preterm birth and pre-eclampsia, Tommy’s also funds projects that research the effects of lifestyle and well-being on pregnancy and on the later life of the child.

  • Team of researchers

    Research into stillbirth

    When a baby dies after 24 weeks of gestation, it is called a stillbirth. Nearly 3000 families a year get the devastating news that their baby is not alive. Our research is helping to change this.

  • Nurse monitoring premature baby in hospital

    Research into premature birth

    Around 60,000 babies are born prematurely each year in the UK. These babies are vulnerable – they are born before they have grown to cope with the outside world. Tommy’s is saving lives by researching how we can prevent premature births by finding those at risk early on.

  • Clinical researcher looking at test tube

    Research into miscarriage

    Miscarriage is the most common complication of pregnancy with 1 in 4 women experiencing at least 1 miscarriage during their reproductive lifetime. This is a quarter of all mothers-to-be, a quarter of all families affected by loss.

News and views from Tommy's

    Was this information useful?

    Yes No


    Please note that these comments are monitored but not answered by Tommy’s. Please call your GP or maternity unit if you have concerns about your health or your baby’s health.

    Your comment

    Add new comment