Test Name: Glucose Challenge Test 
Alternate Test Names Diabetes Elimination Test; GCT; Gestational Diabetes Screening Test; Glucose screening Test; OGCT; Oral Glucose Challenge Test 
PLS Test Code GLUCH  Laboratory Biochemistry 
Specimen Blood  Analysis Performed On Plasma 
Container Fluoride oxalate Tube 2 ml  Container colour Grey 
Multiple specimens  
Required Volume Adult (mL) Req Vol Paediatric (mL)
Reference Ranges  
Turnaround Time Routine 8 Hours  Turnaround Time Urgent  
Turnaround Other  
Days test is performed Daily  Transport Room temperature 
Special Requirements This test is only performed on pregnant women. 
Patient Preparation Nil. No dietary restrictions. 
Collection Instructions Blood glucose levels should be checked using a glucose meter prior to the 75gms of glucose being given. The result must be recorded on the request form on labels that are available from stores. If the pre-dose glucose is > 9.0 mmol/L and <11.1 mmol/L, consult the patient's doctor as a fasting plasma glucose or GTT is probably indicated. If the pre-dose glucose is >11.0 mmol/L talk to the requesting clinical before proceeding and indicate that it is the recommendation of St Vincent's Pathology that a fasting glucose, requested alone or as part of a GTT, is required as the next step. 1. Administer 75 gm glucose drink to patient. (Use only glucose drink from St. Vincent's Pathology stores Department). Glucose drink must be completed within 10 minutes. 2. Collect blood 1 hour after the COMPLETION of the glucose drink. Label tube with Surname, first name, D.O.B. and date and time of collection. Some referring clinicians may want a variant of this test, in such cases, follow the clinician's instructions. 
Clinical Information  
Sent to Reference Laboratory No 
Ref Laboratory Name  
Estimated Patient Fee N/A 
Last Updated 25-Aug-2006 (Version: 1.00)