Normal 1-Hour Post-Load Glucose Value After 75g OGTT

Context-Specific Normal Values

The American College of Obstetricians and Gynecologists recommends a normal 1-hour plasma glucose value after a 75-gram OGTT of less than 180 mg/dL, with values ≥180 mg/dL indicating gestational diabetes in pregnancy or increased risk for future diabetes in non-pregnant individuals 1, 2
The diagnostic threshold for gestational diabetes is 180 mg/dL, any value at or above this level indicates gestational diabetes when using the one-step approach 1, 3, 4
The International Association of Diabetes and Pregnancy Study Groups established this cutoff based on pregnancy outcome data rather than future diabetes risk 4
The HAPO study demonstrated continuous increases in adverse pregnancy outcomes as 1-hour glucose rises 1

The American Academy of Family Physicians notes that the 1-hour measurement is not routinely used for diabetes diagnosis outside of pregnancy, standard diagnostic criteria rely on fasting glucose ≥126 mg/dL or 2-hour glucose ≥200 mg/dL 2, 5
For gestational diabetes, only one elevated value is required for diagnosis using the one-step approach, though the two-step approach requires at least two abnormal values 2, 4, 6

Measuring 1-hour glucose during OGTT provides additional prognostic information, including identifying individuals who would be missed by fasting glucose alone and helping to stratify cardiovascular and mortality risk 1, 2