What does a 1-hour glucose screen result of hyperglycemia indicate and how is it managed?

From the Guidelines

A 1-hour glucose screen result of 242 indicates a high risk for gestational diabetes and necessitates immediate follow-up testing with a 100-g oral glucose tolerance test (OGTT) to confirm the diagnosis. This initial positive screen suggests that the body may not be properly processing glucose during pregnancy, which can lead to various complications for both the mother and the child if left unmanaged 1. The American College of Obstetricians and Gynecologists (ACOG) recommends using a threshold of 130,135, or 140 mg/dL for the 1-h 50-g glucose load test, and since the result of 242 exceeds these thresholds, further testing is required to determine the presence of gestational diabetes mellitus (GDM) 1.

Key Points for Management:

• The diagnosis of GDM is made when at least two of the following four plasma glucose levels (measured fasting and at 1,2, and 3 h during OGTT) are met or exceeded:
  • Fasting: 95 mg/dL
  • 1 h: 180 mg/dL
  • 2 h: 155 mg/dL
  • 3 h: 140 mg/dL
• Management begins with comprehensive education about blood glucose monitoring and nutritional counseling focused on carbohydrate distribution throughout the day.
• Most women can control their glucose levels through dietary modifications and regular physical activity.
• If lifestyle changes are insufficient, medication therapy may be initiated, with insulin being the first-line pharmacological treatment.
• Regular monitoring of blood glucose levels (fasting and 1-hour postprandial) is essential, with target values of <95 mg/dL fasting and <140 mg/dL one hour after meals.

Given the high result of the 1-hour glucose screen, it is crucial to proceed with the diagnostic testing and, if diagnosed with GDM, to manage the condition effectively to minimize risks to both the mother and the child, including macrosomia, birth trauma, neonatal hypoglycemia, and future diabetes 1.

From the FDA Drug Label

Hyperglycemia (too much glucose in the blood) may develop if your body has too little insulin Hyperglycemia can be brought about by any of the following: Omitting your insulin or taking less than your doctor has prescribed. In patients with type 1 or insulin-dependent diabetes, prolonged hyperglycemia can result in DKA (a life-threatening emergency)

A 1-hour glucose screen result of 242 indicates hyperglycemia. This means that the blood glucose level is higher than normal.

• Hyperglycemia can be caused by various factors, including omitting insulin or taking less than prescribed, eating more than the meal plan suggests, or developing a fever or infection.
• If left uncorrected, hyperglycemia can lead to serious complications, such as Diabetic Ketoacidosis (DKA), which is a life-threatening emergency.
• Management of hyperglycemia typically involves adjusting insulin doses, meal plans, and/or exercise programs under the guidance of a healthcare provider 2.

From the Research

Understanding 1-Hour Glucose Screen Results

A 1-hour glucose screen result of 242 indicates hyperglycemia, which may suggest an increased risk of gestational diabetes mellitus (GDM) 3, 4.

Indications and Management

• The 1-hour glucose challenge test is commonly used to screen for GDM, with a cutoff point of 140 mg/dL 3, 4.
• A result of 242 exceeds this threshold, indicating the need for further testing, such as a 2-hour oral glucose tolerance test (OGTT) 5.
• Women with hyperglycemia during pregnancy are at increased risk of adverse outcomes, including fetal macrosomia and gestational hypertension 3, 5.
• Management of GDM typically involves lifestyle modifications, such as dietary changes and increased physical activity, and may also include insulin therapy or other medications 5, 6.

Predicting Adverse Pregnancy Outcomes

• The glucose response pattern in the 75g OGTT can predict adverse perinatal outcomes, including fetal growth restriction and macrosomia 5.
• Women with isolated fasting hyperglycemia (GDM-IFH) or combined hyperglycemia (GDM-CH) are at higher risk of adverse outcomes, including primary cesarean section and large for gestational age (LGA) newborns 5.
• Isolated post-load hyperglycemia (GDM-IPH) is associated with an increased risk of emergent cesarean section and small for gestational age (SGA) newborns 5.

Screening Recommendations

• Universal screening for GDM is recommended, using a 1-hour plasma glucose level after a 50g oral glucose challenge 4.
• The screening threshold should be no higher than 140 mg/dL to maintain sensitivity 4.
• Women with a history of GDM or other risk factors may require more frequent or earlier screening 3, 4.