Authors' objectives: This report aims to identify and summarise evidence that addresses the following question: what is the clinical and cost effectiveness of continuous glucose monitoring (CGM) in pregnant women with type 1 diabetes?

Authors' results and conclusions: There is published evidence from 4 randomised clinical trials that compared the clinical effectiveness of CGM (used as an adjunct to self-monitoring of blood glucose (SMBG)) to SMBG alone in pregnant women with type 1 diabetes. All of the studies used CGM systems manufactured by Medtronic, but in the older trials the systems used have now been superseded by newer iterations and may not, therefore, be entirely representative of current clinical practice. The evidence suggests that the use of CGM leads to a significant improvement in maternal glycaemic control, as measured by glycosylated haemoglobin levels, and a reduction in the incidence of pre-eclampsia. In the neonate, the use of CGM is associated with a significant reduction in hypoglycaemia, and incidence or duration of ICU admission. The evidence leaves uncertainty as to whether CGM positively influences other outcomes, such as the need for caesarean section and the incidence of pregnancy-induced hypertension, miscarriage, increased birthweight and neonatal mortality/stillbirth. Very limited evidence exists to compare CGM to flash glucose monitoring in pregnant women with type 1 diabetes, and the relative effectiveness of these two interventions in this population is therefore uncertain. One economic study was identified that analysed the overall costs associated with the use of CGM compared to standard management in pregnant women with type 1 diabetes. Cost modelling was undertaken to estimate the overall resource impact of CGM, used as an adjunct to SMBG, compared to SMBG alone on the basis of the results of this study and in the context of clinical practice in NHS Wales. The results showed that CGM is likely to lead to overall costs savings of approximately £1,029 per pregnancy, with the cost savings largely driven by a reduction in the incidence and duration of neonatal ICU admission.

Authors' recommendations: The case for adopting continuous glucose monitoring in pregnant women with type 1 diabetes is supported by the evidence. The use of continuous glucose monitoring during pregnancy improves glycaemic control and reduces the incidence of pre-eclampsia in the mother as compared to self-monitoring of blood glucose. Continuous glucose monitoring reduces neonatal hypoglycaemia and the need and duration of neonatal intensive care stay. Cost modelling estimates that the use of continuous glucose monitoring in type 1 diabetic mothers will lead to cost savings of £1,029 per pregnancy as compared to self-monitoring of blood glucose, with the cost savings largely driven by a reduction in neonatal intensive care requirements.

Authors' methods: The Evidence Appraisal Report is based on a literature search (strategy available on request) for published clinical and economic evidence on the health technology of interest. It is not a full systematic review but aims to identify the best available evidence on the health technology of interest. Researchers critically evaluate and synthesise this evidence. We include the following clinical evidence in order of priority: systematic reviews; randomised trials; non-randomised trials. We only include evidence for “lower priority” evidence where outcomes are not reported by a “higher priority” source. We also search for economic evaluations or original research that can form the basis of an assessment of costs/cost comparison. We carry out various levels of economic evaluation, according to the evidence that is available to inform this.

Project Status: Completed

Year Published: 2019

URL for published report: https://www.healthtechnology.wales/reports-guidance/continuous-glucose-monitoring-in-pregnancy/

English language abstract: An English language summary is available

Publication Type: Rapid Review

Country: Wales, United Kingdom

Organisation Name: Health Technology Wales

Contact Address: c/o Digital Health Care Wales, 21 Cowbridge Road East Cardiff CF11 9AD

Contact Name: Susan Myles, PhD

Contact Email: healthtechnology@wales.nhs.uk

Copyright: Health Technology Wales