Current treatment of diabetes in pregnancy relies on intermittent self-monitoring of blood glucoses using finger sticks to monitor capillary blood glucoses. Continuous glucose monitoring (CGM) systems are an emerging technology that allow frequent glucose measurements (every 5 min) and the ability to monitor glucose trends in real time. Although these devices are currently expensive and mildly invasive to use, there is huge potential for their use in both the research and clinical realms. From a research perspective, there is the potential to better understand glucose metabolism in pregnancy, both in patients with and without diabetes. For the treating clinician, CGM has the potential to improve detection of hyperglycemic excursions as well as asymptomatic hypoglycemia and the data to improve management of glucose levels in diabetes patients. In this article, we review current literature examining use of CGM in both research and clinical applications.
HuntKJSchullerKL, The increasing prevalence of diabetes in pregnancy. Obstet Gynecol Clin North Am.2007;34 (2): 173–99.
3.
NoldJLGeorgieffMK, Infants of diabetic mothers. Pediatr Clin North Am.2004;51 (3): 619–37, viii.
4.
HAPO Study Cooperative Research Group, MetzgerBELoweLPDyerARTrimbleERChaovarindrUCoustanDRHaddenDRMcCanceDRHodMMcIntyreHDOatsJJPerssonBRogersMSSacksDA, Hyperglycemia and adverse pregnancy outcomes. N Engl J Med.2008;358 (19): 1991–2002.
LearyJPettittDJJovanovicL.Gestational diabetes guidelines in a HAPO world. Best Pract Res Clin Endocrinol Metab.2010;24 (4): 673–85.
7.
CrowtherCAHillerJEMossJRMcPheeAJJeffriesWSRobinsonJS; Australian Carbohydrate Intolerance Study in Pregnant Women (ACHOIS) Trial Group. Effect of treatment of gestational diabetes mellitus on pregnancy outcomes. N Engl J Med.2005;352 (24): 2477–86.
8.
LandonMBSpongCYThomECarpenterMWRaminSMCaseyBWapnerRJVarnerMWRouseDJThorpJMJrSciscioneACatalanoPHarperMSaadeGLainKYSorokinYPeacemanAMTolosaJEAndersonGB; Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. A multicenter, randomized trial of treatment for mild gestational diabetes. N Engl J Med.2009;361 (14): 1339–48.
9.
SuhonenLHiilesmaaVTeramoK.Glycaemic control during early pregnancy and fetal malformations in women with type I diabetes mellitus. Diabetologia.2000;43 (1): 79–82.
10.
TempleRAldridgeVGreenwoodRHeyburnPSampsonMStanleyK.Association between outcome of pregnancy and glycaemic control in early pregnancy in type 1 diabetes: Population based study. BMJ.2002;325 (7375): 1275–6.
11.
American Diabetes Association. Standards of medical care in diabetes–2012. Diabetes Care.2012;35Suppl 1: S11–63.
KovatchevBAndersonSHeinemannLClarkeW.Comparison of the numerical and clinical accuracy of four continuous glucose monitors. Diabetes Care.2008;31 (6): 1160–4.
14.
GrossTMTer VeerA. Continuous glucose monitoring in previously unstudied population subgroups. Diabetes Technol Ther.2000;2Suppl 1: S27–34.
15.
YogevYBen-HaroushAChenRKaplanBPhillipMHodM.Continuous glucose monitoring for treatment adjustment in diabetic pregnancies–a pilot study. Diabet Med.2003;20 (7): 558–62.
16.
KerssenAde ValkHWVisserGH, The Continuous Glucose Monitoring System during pregnancy of women with type 1 diabetes mellitus: Accuracy assessment. Diabetes Technol Ther.2004;6 (5): 645–51.
17.
KerssenADe ValkHWVisserGH, Validation of the Continuous Glucose Monitoring System (CGMS) by the use of two CGMS simultaneously in pregnant women with type 1 diabetes mellitus. Diabetes Technol Ther.2005;7 (5): 699–709.
18.
BraukerJMatsubaraB.Comparison of the numerical and clinical accuracy of four continuous glucose monitors: Response to Kovatchev et al. Diabetes Care.2008;31 (10): e80–1.
19.
MurphyHRElleriDAllenJMHarrisJSimmonsDRaymanGTempleRDungerDBHaidarANodaleMWilinskaMEHovorkaR.Closed-loop insulin delivery during pregnancy complicated by type 1 diabetes. Diabetes Care.2011;34 (2): 406–11.
20.
YogevYBen-HaroushAChenRRosennBHodMLangerO.Diurnal glycemic profile in obese and normal weight nondiabetic pregnant women. Am J Obstet Gynecol.2004;191 (3): 949–53.
21.
SiegmundTRadNTRitterathCSiebertGHenrichWBuhlingKJ, Longitudinal changes in the continuous glucose profile measured by the CGMS in healthy pregnant women and determination of cut-off values. Eur J Obstet Gynecol Reprod Biol.2008;139 (1): 46–52.
22.
HarmonKAGerardLJensenDRKealeyEHHernandezTLReeceMSBarbourLABessesenDH, Continuous glucose profiles in obese and normal-weight pregnant women on a controlled diet: Metabolic determinants of fetal growth. Diabetes Care.2011;34 (10): 2198–204.
23.
MurphyHRRaymanGLewisKKellySJohalBDuffieldKFowlerDCampbellPJTempleRC, Effectiveness of continuous glucose monitoring in pregnant women with diabetes: Randomised clinical trial. BMJ.2008;337: a1680.
24.
MurphyHRRaymanGDuffieldKLewisKSKellySJohalBFowlerDTempleRC, Changes in the glycemic profiles of women with type 1 and type 2 diabetes during pregnancy. Diabetes Care.2007;30 (11): 2785–91.
25.
BühlingKJKurzidimBWolfCWohlfarthKMahmoudiMWäscherCSiebertGDudenhausenJW, Introductory experience with the continuous glucose monitoring system (CGMS; Medtronic Minimed) in detecting hyperglycemia by comparing the self-monitoring of blood glucose (SMBG) in non-pregnant women and in pregnant women with impaired glucose tolerance and gestational diabetes. Exp Clin Endocrinol Diabetes.2004;112 (10): 556–60.
26.
KestiläKKEkbladUURönnemaaT.Continuous glucose monitoring versus self-monitoring of blood glucose in the treatment of gestational diabetes mellitus. Diabetes Res Clin Pract.2007;77 (2): 174–9.
27.
Ben-HaroushAYogevYChenRRosennBHodMLangerO.The postprandial glucose profile in the diabetic pregnancy. Am J Obstet Gynecol.2004;191 (2): 576–81.
28.
BühlingKJWinkelTWolfCKurzidimBMahmoudiMWohlfarthKWäscherCSchinkTDudenhausenJW, Optimal timing for postprandial glucose measurement in pregnant women with diabetes and a non-diabetic pregnant population evaluated by the Continuous Glucose Monitoring System (CGMS). J Perinat Med.2005;33 (2): 125–31.
29.
CyprykKPertyńska-MarczewskaMSzymczakWWilcyńskiJLewińskiA.Evaluation of metabolic control in women with gestational diabetes mellitus by the continuous glucose monitoring system: A pilot study. Endocr Pract.2006;12 (3): 245–50.
30.
KerssenAde ValkHWVisserGH, Forty-eight-hour first-trimester glucose profiles in women with type 1 diabetes mellitus: A report of three cases of congenital malformation. Prenat Diagn.2006;26 (2): 123–7.
KerssenAde ValkHWVisserGH, Increased second trimester maternal glucose levels are related to extremely large-for-gestational-age infants in women with type 1 diabetes. Diabetes Care.2007;30 (5): 1069–74.
33.
McLachlanKJenkinsAO'NealD.The role of continuous glucose monitoring in clinical decision-making in diabetes in pregnancy. Aust N Z J Obstet Gynaecol.2007;47 (3): 186–90.
34.
YogevYChenRBen-HaroushAPhillipMJovanovicLHodM.Continuous glucose monitoring for the evaluation of gravid women with type 1 diabetes mellitus. Obstet Gynecol.2003;101 (4): 633–8.
35.
BergenstalRMTamborlaneWVAhmannABuseJBDaileyGDavisSNJoyceCPeoplesTPerkinsBAWelshJBWilliSMWoodMA; STAR 3 Study Group. Effectiveness of sensor-augmented insulin-pump therapy in type 1 diabetes. N Engl J Med.2010;363 (4): 311–20.
36.
PetrovskiGDimitrovskiCBogoevMMilenkovicTAhmetiIBitovskaI.Is there a difference in pregnancy and glycemic outcome in patients with type 1 diabetes on insulin pump with constant or intermittent glucose monitoring? A pilot study. Diabetes Technol Ther.2011;13 (11): 1109–13.
37.
MurphyHRKumareswaranKElleriDAllenJMCaldwellKBiagioniMSimmonsDDungerDBNodaleMWilinskaMEAmielSAHovorkaR.Safety and efficacy of 24-h closed-loop insulin delivery in well-controlled pregnant women with type 1 diabetes: A randomized crossover case series. Diabetes Care.2011;34 (12): 2527–9.
38.
HirschIB, Low glucose suspend: Ready for prime time?Diabetes Technol Ther.2012;14 (3): 201–2.
39.
RosennBMMiodovnikMHolcbergGKhouryJCSiddiqiTA, Hypoglycemia: The price of intensive insulin therapy for pregnant women with insulin-dependent diabetes mellitus. Obstet Gynecol.1995;85 (3): 417–22.
40.
GargSZisserHSchwartzSBaileyTKaplanREllisSJovanovicL.Improvement in glycemic excursions with a transcutaneous, real-time continuous glucose sensor: A randomized controlled trial. Diabetes Care.2006;29 (1): 44–50.
41.
TanenbergRBodeBLaneWLevetanCMestmanJHarmelAPTobianJGrossTMastrototaroJ.Use of the continuous glucose monitoring system to guide therapy in patients with insulin-treated diabetes: A randomized controlled trial. Mayo Clin Proc.2004;79 (12): 1521–6.
42.
AkazawaMAkazawaSHashimotoMAkashiMYamazakiHTaharaDYamamotoHYamaguchiYNakanishiTNagatakiS.Effects of brief exposure to insulin-induced hypoglycemic serum during organogenesis in rat embryo culture. Diabetes.1989;38 (12): 1573–8.
43.
AkazawaSAkazawaMHashimotoMYamaguchiYKuriyaNToyamaKUedaYNakanishiTMoriTMiyakeS.Effects of hypoglycaemia on early embryogenesis in rat embryo organ culture. Diabetologia.1987;30 (10): 791–6.
