The global epidemic of type 2 diabetes (T2DM) in young people has contributed to an increase in pregestational diabetes in pregnancy.1-3 Maternal glycemia is a key modifiable risk factor to optimize pregnancy outcomes, with new diabetes technology potentially contributing to improved glycemic levels and neonatal outcomes. 4 There are limited data regarding intermittently scanned continuous glucose monitoring (iscCGM) in pregnancy for women with T2DM. We conducted a prospective pilot to assess the feasibility and acceptability of iscCGM in pregnancy among women with pre-existing T2DM.
During the intervention period (2019-2021), 78 women were referred to a regional diabetes in pregnancy service in northern Australia. Eighteen (23%) women were excluded due to late referral (>30 weeks gestation) and three women declined. Fifty-seven women enrolled and were given a FreeStyle Libre glucose monitor and sensors for the pregnancy duration. Thirty-four (75%) women were Aboriginal and/or Torres Strait Islander, 14 (31%) lived >100 km from the city, and 40 (91%) used insulin. Fifty (88%) completed the satisfaction questionnaire and 45 (79%) used iscCGM for ≥2 weeks. Mean sensor use was 12 (range = 0-32, SD = 9.2) weeks, with 40% commencing in first trimester. In the final two weeks of use, mean sensor activity time was 60% (range = 12%-98%, SD = 22%), mean number of scans per day was 4.3 (SD 3.3), and the proportion of women with sensor activity >75% was 12 (27%).
Most participants found iscCGM was worthwhile and easy to use (Figure 1); 47 (94%) would recommend iscCGM to others. Self-reported frequency of glucose testing four times per day increased from 36% to 68% (P = .001), compared with prior finger-stick measurements. Participants reported that Diabetes Educators gave the most useful device education, of all health professionals encountered. Reasons for discontinuation included rash, sensors falling off early, and distrust of accuracy. Women who discontinued use had similar demographic characteristics, but less insulin prescribed than those who continued use (67% vs 91%, P = .04). Half the women reported thinking about diabetes “more than I wanted to” indicating the amount of information may have been excessive for some, in particular those using less complex insulin regimes.
Figure 1.
Questionnaire results.
Abbreviations: W, worthwhileness; B, behavioral burden; E, emotional burden; O, openness: questions from the Glucose Monitoring System Satisfaction Survey. 5
a42 patients used the iscCGM >2 weeks, 8 patients had discontinued use.
Feasibility assessment revealed that nearly all eligible women agreed to participate and were able to use the technology. Ethnicity and remoteness were not necessarily barriers to use. However, in this real-world setting, late referrals (23%), discontinuation (21%), and variability of use meant that few patients used iscCGM for the entire pregnancy. This differs considerably to studies investigating continuous glucose monitoring for women with type 1 diabetes in pregnancy, where all patients commenced in the first trimester and >70% had sensor activity >75%. 4 Improving referral pathways, 6 culturally appropriate health systems,3,6 and ensuring access to diabetes educator time and expertise are essential to support optimal use of this technology.
This study suggests that iscCGM could be a useful and well-received tool for improving glycemic control in women with T2DM in pregnancy. Further rigorous study by way of randomized controlled testing is needed to confirm this impression.
Acknowledgments
The authors wish to thank Queensland Health nurses Deborah Schafer, Debra Clare, and Tiffany Conway for their assistance with study coordination and data collection; Georgina Tabuai for giving Aboriginal and Torres Strait Islander cultural advice; and Zhiqiang Wang (Menzies School of Health Research) for statistical support. They wish to thank Kirby Murtha, Federica Barzi, and Chief Investigators of the NHMRC Global Alliance for Chronic Diseases grant (1092968) for their contributions to the FNQ Diabetes in Pregnancy Clinical Register (which provided demographic data), including those not named as authors: Alex Brown, Christine Connors, Kerin O’Dea, Jonathan Shaw, Jeremy Oats, Paul Zimmet, Mark Wenitong, and Anthony Hanley.
Footnotes
Abbreviations: iscCGM, intermittently scanned continuous glucose monitoring; SD, standard deviation; T2DM, type 2 diabetes mellitus.
Authorship Confirmation Statement: All authors meet the authorship definition as defined by the International Committee of Medical Journal Editors. All authors have approved the final manuscript.
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The Freestyle Libre glucose monitors and nursing support time were supported by a Queensland Health (state government) New Technology Funding and Evaluation Program. LM-B was supported by a National Health and Medical Research Council (NHMRC) investigator grant 1194698. AM was supported by a NHMRC postgraduate scholarship 1168623. The FNQ Diabetes in Pregnancy Clinical Register was supported by an NHMRC Global Alliance for Chronic Diseases grant 1092968. The views expressed in this publication are those of the authors and do not reflect the views of the NHMRC or Queensland Health. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.
ORCID iD: Anna McLean 
https://orcid.org/0000-0001-5578-0188
References
- 1. Chivese T, Hoegfeldt CA, Werfalli M, et al. IDF Diabetes Atlas: the prevalence of pre-existing diabetes in pregnancy—a systematic review and meta-analysis of studies published during 2010-2020. Diabetes Res Clin Pract. 2022;183:109049. [DOI] [PubMed] [Google Scholar]
- 2. Voaklander B, Rowe S, Sanni O, Campbell S, Eurich D, Ospina MB. Prevalence of diabetes in pregnancy among Indigenous women in Australia, Canada, New Zealand, and the USA: a systematic review and meta-analysis. Lancet Glob Health. 2020;8(5):e681-e698. [DOI] [PubMed] [Google Scholar]
- 3. Murphy HR, Howgate C, O’Keefe J, et al. Characteristics and outcomes of pregnant women with type 1 or type 2 diabetes: a 5-year national population-based cohort study. Lancet Diabetes Endocrinol. 2021;9(3):153-164. [DOI] [PubMed] [Google Scholar]
- 4. Feig DS, Donovan LE, Corcoy R, et al. Continuous glucose monitoring in pregnant women with type 1 diabetes (CONCEPTT): a multicentre international randomised controlled trial. Lancet. 2017;390(10110):2347-2359. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5. Polonsky WH, Fisher L, Hessler D, Edelman SV. Development of a new measure for assessing glucose monitoring device-related treatment satisfaction and quality of life. Diabetes Technol Ther. 2015;17(9):657-663. [DOI] [PubMed] [Google Scholar]
- 6. MacKay D, Freeman N, Boyle JA, et al. Improving systems of prenatal and postpartum care for hyperglycemia in pregnancy: a process evaluation. Int J Gynaecol Obstet. 2021;155(2):179-194. [DOI] [PubMed] [Google Scholar]