Effectiveness of continuous glucose monitoring in pregnant women with diabetes: randomised clinical trial.
OBJECTIVE
To evaluate the effectiveness of continuous glucose monitoring during pregnancy on maternal glycaemic control, infant birth weight, and risk of macrosomia in women with type 1 and type 2 diabetes.


METHODS
Prospective, open label randomised controlled trial.


METHODS
Two secondary care multidisciplinary obstetric clinics for diabetes in the United Kingdom.


METHODS
71 women with type 1 diabetes (n=46) or type 2 diabetes (n=25) allocated to antenatal care plus continuous glucose monitoring (n=38) or to standard antenatal care (n=33).


METHODS
Continuous glucose monitoring was used as an educational tool to inform shared decision making and future therapeutic changes at intervals of 4-6 weeks during pregnancy. All other aspects of antenatal care were equal between the groups.


METHODS
The primary outcome was maternal glycaemic control during the second and third trimesters from measurements of HbA(1c) levels every four weeks. Secondary outcomes were birth weight and risk of macrosomia using birthweight standard deviation scores and customised birthweight centiles. Statistical analyses were done on an intention to treat basis.


RESULTS
Women randomised to continuous glucose monitoring had lower mean HbA(1c) levels from 32 to 36 weeks' gestation compared with women randomised to standard antenatal care: 5.8% (SD 0.6) v 6.4% (SD 0.7). Compared with infants of mothers in the control arm those of mothers in the intervention arm had decreased mean birthweight standard deviation scores (0.9 v 1.6; effect size 0.7 SD, 95% confidence interval 0.0 to 1.3), decreased median customised birthweight centiles (69% v 93%), and a reduced risk of macrosomia (odds ratio 0.36, 95% confidence interval 0.13 to 0.98).


CONCLUSIONS
Continuous glucose monitoring during pregnancy is associated with improved glycaemic control in the third trimester, lower birth weight, and reduced risk of macrosomia.


BACKGROUND
Current Controlled Trials ISRCTN84461581.
Murphy
Helen R
HR
Department of Diabetes and Endocrinology, Ipswich Hospital NHS Trust, Ipswich IP4 5PD. Helen.Murphy@ipswichhospital.nhs.uk
Rayman
Gerry
G
Lewis
Karen
K
Kelly
Susan
S
Johal
Balroop
B
Duffield
Katherine
K
Fowler
Duncan
D
Campbell
Peter J
PJ
Temple
Rosemary C
RC
D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D015190:Blood Glucose Self-Monitoring; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D005320:Fetal Macrosomia / Q000097:blood / Q000517:prevention & control*; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D006943:Hyperglycemia / Q000517:prevention & control; D008875:Middle Aged; D011247:Pregnancy; D011256:Pregnancy Outcome; D011254:Pregnancy in Diabetics / Q000097:blood*; D011295:Prenatal Care / Q000379:methods*; D011296:Prenatal Diagnosis; D011446:Prospective Studies; D013997:Time Factors
D001786:Blood Glucose; D006442:Glycated Hemoglobin