Life-course management of gestational diabetes mellitus: A narrative review

Table 1 Summary of diagnostic thresholds for gestational diabetes mellitus according to different guidelines

Guideline	Test type	Timing	Fasting threshold (mg/dL)	1-hour	2-hour	Diagnosis criteria
IADPSG	75-g OGTT	24-28 weeks	≥ 92	≥ 180	≥ 153	Any one abnormal
ADA	75-g OGTT	24-28 weeks	≥ 95	≥ 180	≥ 155	Any two abnormal
ACOG	50-g GCT + 100-g OGTT	24-28 weeks	≥ 95	≥ 180	≥ 155	Two-step approach
WHO	75-g OGTT	24-28 weeks	≥ 92	-	≥ 153	Any one abnormal

Thresholds are presented in both mmol/L and mg/dL. A diagnosis of gestational diabetes mellitus is established when one or more values exceed the cut-off in the one-step approach, or when two or more values exceed the cut-offs in the two-step approach. ADA: American diabetes association; IADPSG: International Association of Diabetes and Pregnancy Study Groups; ACOG: American College of Obstetricians and Gynecologists; WHO: World Health Organization; OGTT: Oral glucose tolerance test; GCT: Glucose challenge test.