Continuous glucose monitoring targets in type 1 diabetes pregnancy:every 5% time in range matters

Murphy, Helen R. (2019) Continuous glucose monitoring targets in type 1 diabetes pregnancy:every 5% time in range matters. Diabetologia, 62 (7). pp. 1123-1128. ISSN 0012-186X

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With randomised trial data confirming that continuous glucose monitoring (CGM) is associated with improvements in maternal glucose control and neonatal health outcomes, CGM is increasingly used in antenatal care. Across pregnancy, the ambition is to increase the CGM time in range (TIR), while reducing time above range (TAR), time below range (TBR) and glycaemic variability measures. Pregnant women with type 1 diabetes currently spend, on average, 50% (12 h), 55% (13 h) and 60% (14 h) in the target range of 3.5–7.8 mmol/l (63–140 mg/dl) during the first, second and third trimesters, respectively. Hyperglycaemia, as measured by TAR, reduces from 40% (10 h) to 33% (8 h) during the first to third trimester. A TIR of >70% (16 h, 48 min) and a TAR of <25% (6 h) is achieved only in the final weeks of pregnancy. CGM TBR data are particularly sensor dependent, but regardless of the threshold used for individual patients, spending ≥4% of time (1 h) below 3.5 mmol/l or ≥1% of time (15 min) below 3.0 mmol/l is not recommended. While maternal hyperglycaemia is a well-established risk factor for obstetric and neonatal complications, CGM-based risk factors are emerging. A 5% lower TIR and 5% higher TAR during the second and third trimesters is associated with increased risk of large for gestational age infants, neonatal hypoglycaemia and neonatal intensive care unit admissions. For optimal neonatal outcomes, women and clinicians should aim for a TIR of >70% (16 h, 48 min) and a TAR of <25% (6 h), from as early as possible during pregnancy.

Item Type: Article
Uncontrolled Keywords: continuous glucose monitoring,hyperglycaemia,pregnancy,type 1 diabetes,internal medicine,endocrinology, diabetes and metabolism,sdg 3 - good health and well-being ,/dk/atira/pure/subjectarea/asjc/2700/2724
Faculty \ School: Faculty of Medicine and Health Sciences > Norwich Medical School
UEA Research Groups: Faculty of Medicine and Health Sciences > Research Groups > Cardiovascular and Metabolic Health
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Depositing User: LivePure Connector
Date Deposited: 21 Jun 2019 08:30
Last Modified: 22 Oct 2022 04:53
DOI: 10.1007/s00125-019-4904-3

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