OGT Cheat Sheet 2026

The 30 highest-yield OGT facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is the recommended screening week range for gestational diabetes testing in pregnant women without prior risk factors? → 24–28 weeks
2. Which immunosuppressant used in organ transplant patients commonly causes post-transplant diabetes and abnormal OGTT? → Cyclosporine
3. Which hormone's function is primarily assessed by the OGTT? → Insulin
4. Which glucose value in the 50 g non-fasting GCT always warrants skipping the diagnostic OGTT and confirming GDM directly? → ≥200 mg/dL
5. Niacin (nicotinic acid) at pharmacological doses used for dyslipidemia can affect OGTT by: → Raising plasma glucose through insulin resistance
6. Which instruction is correct regarding smoking before an OGTT? → Patients should refrain from smoking during the test period
7. According to ADA criteria, what is the 2-hour plasma glucose value that confirms diabetes during an OGTT? → ≥200 mg/dL
8. How long after drinking the glucose solution are blood samples typically taken in the OGTT? → Immediately and at 1, 2, and 3 hours
9. How long after drinking the glucose solution are blood samples typically taken in the OGTT? → Immediately and at 1, 2, and 3 hours
10. Which class of medication used for HIV treatment is specifically associated with decreased peripheral glucose disposal on OGTT? → Protease inhibitors
11. A patient with GDM who delivers a healthy baby should be counseled that GDM resolves postpartum but increases risk of: → Type 2 diabetes and cardiovascular disease later in life
12. What term describes the liver's production of new glucose from non-carbohydrate precursors such as amino acids? → Gluconeogenesis
13. Patients should inform their provider about all medications before an OGTT because: → Some drugs can cause false-positive or false-negative glucose readings
14. How many hours must a patient fast before a standard oral glucose tolerance test (OGTT)? → 10–12 hours
15. What should a patient avoid before taking the OGTT to ensure accurate results? → Physical exercise
16. HIV antiretroviral therapy, particularly protease inhibitors, can affect OGTT by: → Causing lipodystrophy and insulin resistance, raising OGTT values
17. A 2-hour glucose of 138 mg/dL on a standard OGTT would be categorized as: → Normal
18. Which hormone primarily causes physiological insulin resistance during the second and third trimesters of pregnancy? → Human placental lactogen (hPL)
19. Thiazide diuretics affect OGTT results by: → Raising blood glucose by impairing insulin secretion and increasing insulin resistance
20. What blood pressure target is recommended for newly diagnosed type 2 diabetes patients at follow-up? → <140/90 mmHg or <130/80 mmHg (individualized)
21. What is the fasting glucose threshold for GDM diagnosis on the 75 g one-step OGTT (IADPSG criteria)? → ≥92 mg/dL
22. A patient's 1-hour value during a 3-hour GDM OGTT is 195 mg/dL (Carpenter-Coustan threshold: 180 mg/dL). What does this single abnormal value indicate? → The finding is borderline; at least one more abnormal value is needed for diagnosis
23. Alcohol consumption the night before an OGTT can cause: → Falsely low fasting glucose due to inhibition of hepatic gluconeogenesis
24. What HbA1c range does the ADA use to identify prediabetes? → 5.7%–6.4%
25. How much glucose is typically used in the solution for a standard OGTT? → 75 grams
26. Which laboratory value, when checked at a 3-month diabetes follow-up after OGTT diagnosis, indicates inadequate glycemic control? → HbA1c ≥ 8.0%
27. Acute physiological stress such as surgery or serious infection affects OGTT reliability by: → Raising glucose via counter-regulatory hormone release
28. What is the fasting plasma glucose threshold in the Carpenter-Coustan criteria for the 3-hour 100g OGTT? → 95 mg/dL
29. What blood glucose level two hours after the OGTT confirms a diagnosis of diabetes? → 200 mg/dL or higher
30. During the OGTT, what type of solution is the patient required to drink? → Glucose solution