Glucose (blood)


Diagnosis and monitoring of hypoglycaemia or diabetes mellitus

For glucose tolerance tests, please send 0/120 minute samples together, ensuring time of sample draw is indicated on the tubes. If the patient is pregnant, please state this in the clinical details.

Reference ranges:

Age range Reference range (mmol/L)
Fasting All ages/sexes 3 - 6
Random < 30 days 2.5 - 5
Random Adults 3.5 - 9

Derived from Tietz Fundamentals of Clinical Chemistry 5th Ed. 2001

Results outside the reference range do not necessarily indicate disease. Similarly, results within the reference range do not preclude abnormality. Please contact the Duty Biochemist for discussion of individual patient results.

Interpretation of Glucose Tolerance Tests

0 minutes (mmol/L) 120 minutes (mmol/L) Interpretation
< 6.1 and < 7.8 Normal
6.1 - 6.9 and < 7.8 Impaired fasting glucose
< 7.0 and 7.8 - 11.0 Impaired glucose tolerance
≥ 7.0 and/or


Diabetes mellitus

Derived from WHO Definition and Diagnosis of Diabetes Mellitus and Intermediate Hyperglycemia (2006)

Interpretation of Glucose Tolerance Tests in pregnancy

0 minutes (mmol/L) 120 minutes (mmol/L) Interpretation
< 5.5 and < 7.8 Normal
≥ 5.6 and/or ≥ 7.8 Gestational diabetes mellitus

Derived from NICE Guidelines (NG3) Diabetes in Pregnancy - February 2015

Other Comments:

For more information, please see the following:

Glucose - Lab Tests Online
Fasting guidelines

See also: HbA1c, Fructosamine, Insulin, C-peptide

About This Test

Department: Biochemistry


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Turnaround Time:

Within 24 hours