Glucose Tolerance, Gestational Screen 1 Hour (50g)

Abbrev Code:GLU1   
Order Code:LAB3503Order Name:Glucose Tolerance, Gest Screen1 Hour
Synonyms:GTT; Glucose Challenge
Methodology:Bichromatic endpoint, glucose oxidase
St Johns/St Joseph/Woodwinds: Hexokinase
CPT Codes: 82950 x1, 82952 x1
Test Includes:Blood glucose level collected one hour after ingestion of 50 g glucose
Turnaround Time:Performed Mon-Fri, 0700-1700; turnaround time is 2 hours routine, 40 minutes stat.
Special Instructions:This is a screening test usually administered between 24-28 weeks of pregnancy.

Collection Instructions

Optimal Volume:2.5 mL
Minimum\Peds Volume:0.6 mL
Container:Green (lithium heparin, gel), St Johns/St Joseph/Woodwinds - Gray Na Fluoride)
Alternate Containers: Green (lithium heparin, no gel), Red (no gel), Red or gold (gel), St Johns/St Joseph/Woodwinds-Green (lithium heparin, no gel), St Johns/St Joseph/Woodwinds - Red (no gel), St Johns/St Joseph/Woodwinds - Purple (EDTA)
Collection Instructions:Glucose Tolerance Protocol  
Outpatient Laboratory will collect specimens in green top (heparin) or red/black top (gel) tubes to avoid hemolysis.
For Womens Health Clinic:
  1. WHC will drop off request form to be filed in the future order file.
  2. Patient will check into the lab to drink the 50 g glucola (no blood is drawn pre-glucola for the 50 g screen).
  3. OP Lab will set the timer for 1 hour.
  4. OP Lab will send a lab staff to WHC to draw the 1 hour post sample and other labs if needed.
Patient Preparation:Patient does not need to be fasting and needs no preparation. The gestational diabetic screen is performed without regard to last meal or time of day.
Contraindications:If patient becomes ill or vomits, test must be discontinued.

Processing and Shipping

Specimen Processing:Centrifuge and aliquot 1.25 mL, 0.2 mL minimum. Store in refrigerator.
Shipping Instructions:Ship at refrigerated temperature.
Stability:Once separated from cells, Room temperature - 8 hours; refrigerated - 72 hours.
Test Performed at or Referral Lab Chemistry  (M Health Maple Grove Clinic, Range, UMMC-East Bank, Oxboro Bloom, Lakes, Ridges, Northland, Southdale, UMMC/UMMCH-West Bank, Clinics, M Health Clinic and Surgery Center, Grand Itasca, St. Joseph's, St. John's, Woodwinds)


Critical Range:Glucose Tolerance Reference Ranges
Reference Range:Glucose Tolerance Reference Ranges

Click HERE to Report test errors or omissions.
*If no email program is associated with this computer, please contact: for TestID: 3922"