1. The first hospital visit after confirming pregnancy

1) All pregnant women should undergo either fasting plasma glucose (FPG), random plasma glucose, or HbA1c testing at their first hospital visit after confirming pregnancy. [Non-randomized controlled trial, general recommendation]

2) If pregnant women meet any of the following criteria during the first hospital visit after confirming pregnant, they are considered to have pre-existing diabetes—If an individualmeets any of the 2-1) to 2-3) criteria, diagonosis requires two abnormal test results obtained at the same time or these criteria should be confirmed by releat testing on a different day.

2-1) HbA1c ≥6.5%

2-2) 8-hour FPG≥126 mg/dL

2-3) 2-hour plasma glucose during 75-g OGTT ≥200 mg/dL

2-4) Presence of classic symptoms of hyperglycemia (polyuria, polydipsia, and unknown weight loss) with random plasma glucose level ≥200 mg/dL

2. 24 to 28 weeks of gestation

1) Pregnant women who have never been diagnosed with diabetes or gestational diabetes should be tested using one of the following methods between 24 to 28 weeks of pregnancy. [Non-randomized controlled trial, general recommendation]

1-1) 75-g OGTT: gestational diabetes mellitus (GDM) is diagnesd if one or more of the following criteria are met (one-step approach).

- FPG ≥92 mg/dL

- 1-hour plasma glucose during OGTT ≥180 mg/dL

- 2-hour plasma glucose during OGTT ≥153 mg/dL

1-2) If the plasma glucose level measured 1 hour after loadduring a 50-g OGTT is ≥140 mg/dL (≥130 mg/dL for pregnant women at high risk), proceed to a 100-g OGTT; GDM is diagnosed if two or more of the following criteria are met (two-step approach).

- FPG ≥95 mg/dL

- 1-hour plasma glucose during OGTT ≥180 mg/dL

- 2-hour plasma glucose during OGTT ≥155 mg/dL

- 3-hour plasma glucose during OGTT ≥140 mg/dL