Specimen Requirements

Patient Preparation

1. Consult physician for specific orders.
2. Patient should discontinue medication 3 days prior to test, if possible.
3. Patient should be instructed to eat and drink nothing except water for 10 to 14 hours prior to test.
4. Patient should be instructed to refrain from smoking and drinking coffee just before and during test.
 

Procedure
Procedure
1. The patient should be fasting for 8-12 hours.
2. A fasting glucose is drawn and measured.
3. A glucose load of 75 gm is given orally. Adults 12 and older, oral glucose dose must be completely ingested within 5 minutes start to finish.
4. A serum glucose level is drawn at 2 hours per American College of Obstetricians and Gynecologists (ACOG) recommendations.



Preferred: Plasma (heparinized)
Container/tube: Lt Green/Mint top (lithium heparin) tube

Acceptable: Serum
Container/tube: Plain, red-top or gold, serum gel tube

Specimen Volume: 1.0 mL (minimum volume 0.2 mL)