Closed-loop insulin systems are effective for pregnant women with type 1 diabetes

Hybrid closed-loop therapy significantly improves maternal glycaemic control during pregnancy complicated by type 1 diabetes, latest research reveals.

A new study has found that pregnant women using a hybrid closed-loop system spent 2.5 more hours per day in the target blood sugar range compared to those receiving standard therapy.

According to the researchers, no unexpected safety issues were reported with the closed-loop system.

This randomised controlled trial included 124 pregnant women with type 1 diabetes from nine hospitals in England, Scotland and Northern Ireland. Their average age was 31 and 93 per cent of the participants were white.

Before 16 weeks’ gestation, 63 women received a standard insulin pump and 61 received a closed-loop system. Both groups had continuous glucose monitoring on their phone.

The study found that those in the closed-loop group spent 12 per cent more time within the blood sugar target range for pregnant women (3.5 to 7.8 mmol/L) than the participants in the standard pump group.

Additionally, the pregnant women in the closed-loop group spent less time above range (29 per cent) than those in the standard pump group (41 per cent), the research has reported.

Among those who started treatment in their first trimester, the closed-loop group spent five per cent more time in the target range than the standard pump group, according to the results.

Author Helen Murphy, Professor of Medicine, University of East Anglia, said: “This is the news that pregnant women with type 1 diabetes have been waiting for.

“It is great to see advances in diabetes technology deliver such improvements for mothers and infants.”

She added: “In addition to the unprecedented improvements in blood sugars among women using pumps or injections, we found that women who used the closed loop system gained 3.7 kg (approximately 8lbs) less weight during pregnancy.

“Furthermore, the study participants very closely matched pregnant women across the UK in terms of their age, ethnicity, and blood sugar levels.”

Previous research has linked five per cent more time spent within the target blood sugar range with improve pregnancy outcomes, including fewer intensive care admissions.

Faye Riley, Research Communications Manager at Diabetes UK, said: “Pregnancy can be a particularly stressful time for anyone with type 1 diabetes, as it becomes more challenging to manage blood sugar levels, which increases the risk of complications.

“This latest study underlines the clear and compelling benefits of using hybrid closed-loop technology during pregnancy, for both parent and baby.”

The National Institute of Health and Care Excellence (NICE) now recommends closed-loop as an option for all women with type 1 diabetes who are pregnant or planning pregnancy.

Peter Hammond, Consultant Endocrinologist at the Harrogate and District Foundation Trust, said: “In pregnant women with diabetes, our goal is to optimise glucose control as effectively as possible throughout pregnancy with much tighter glycaemic targets than for non-pregnant individuals.

“This study provides convincing evidence that the best way to achieve this control is by offering all pregnant women with type 1 diabetes a hybrid closed-loop insulin delivery system, which is capable of targeting blood glucose levels of 5.5 mmol/L or lower.”

He concluded: “This is a landmark study in terms of how best to optimise glycaemic control in pregnancy and hence maternal and neonatal outcomes for pregnant women with type 1 diabetes.

“Closed-loop insulin delivery will become the gold standard treatment for pregnant women with type 1 diabetes and recently published NICE guidance, has advised that this will be the recommended standard of care.”

For more information and to access the study results, click here.