Postpartum 75-Gram Glucose Tolerance
82951, 82952 (x2)
•Glucose Tolerance, Gestational Diabetes (Fasting, One-hour, Two-hour, and Three-hour)
Diagnose gestational diabetes
Serum or plasma
In 2013,2 the American College of Obstetricians and Gynecologists (ACOG) recommended that all pregnant women be screened for gestational diabetes mellitus (GDM)—whether by patient history, clinical risk factors, or with a 50-gram, one-hour loading test at 24 to 28 weeks of gestation to determine blood glucose levels—and suggested relying on the result of the 100-gram, three-hour oral glucose tolerance test for diagnosis (often referred to as a “two-step” method).
The American Diabetes Association (ADA)1 released standards that vary from the ACOG recommendations. The ADA standards recommend a simplified “one-step” approach to the screen and diagnosis of gestational diabetes mellitus with a 75-gram, two-hour glucose tolerance test. The test according to the ADA recommendations is Gestational Glucose Tolerance Screening and Diagnostics Test (Two-hour, ADA Recommendations)
1 mL serum or plasma each tube
0.5 mL serum or plasma each tube
Gel-barrier tubes (4) or gray-top (sodium fluoride/potassium oxalate plasma) tubes (4)
Draw a fasting blood sugar before administering 100-gram glucose, and draw blood at one, two, and three hours. The subject should remain seated and not smoke throughout the test. Submit 1 mL serum or plasma for fasting, one-hour, two-hour, and three-hour specimens. Separate serum or plasma from cells within 45 minutes of venipuncture. Gray-top tubes only, may be submitted without centrifugation. Label each tube with patient’s name and collection time interval (ie, fasting, one-hour, two-hour, and three-hour).
Maintain specimen at room temperature.
Frozen gray-top tube (frozen plasma from gray-top is acceptable); stressed patient (surgery, infection, corticosteroids) should not have GTT; specimens not labeled with collection time intervals (i.e., fasting, one-hour, two-hour, and three-hour)