The 1-hour glucose screening test is a standard part of prenatal care, typically performed between 24 and 28 weeks of pregnancy. Its purpose is to identify pregnant individuals who may be at an increased risk of developing gestational diabetes, a condition where high blood sugar levels develop or are first recognized during pregnancy.
Understanding Your 1-Hour Glucose Test Result
An elevated result on the 1-hour glucose test does not confirm gestational diabetes; it is a screening test, not a diagnostic one. Many pregnant individuals receive an elevated result on this initial screening. The threshold for an elevated result commonly falls between 130 mg/dL and 140 mg/dL, though specific values can vary by clinic or laboratory.
A result above this threshold means further investigation is needed to determine how the body processes sugar. It is common to have an elevated 1-hour screening result and still not have gestational diabetes after additional testing.
The Next Step: The 3-Hour Glucose Tolerance Test
If your 1-hour glucose screening test shows an elevated blood sugar level, the next step is typically a 3-hour oral glucose tolerance test (OGTT). This test definitively confirms or rules out gestational diabetes by providing a detailed look at how your body processes glucose over a longer period.
The 3-hour OGTT requires you to fast for 8 to 14 hours before the test. Upon arrival at the lab, a baseline blood sample will be drawn to measure your fasting blood glucose level. You will then drink a glucose solution, typically containing 100 grams of glucose, within five minutes.
After consuming the glucose drink, additional blood samples will be drawn at 1-hour, 2-hour, and 3-hour intervals. You must remain at the lab for the entire duration, as physical activity can affect the results. A diagnosis of gestational diabetes is usually made if two or more blood glucose readings meet or exceed specific thresholds. For a 3-hour 100-gram OGTT, common thresholds are: fasting less than 95 mg/dL, 1-hour less than 180 mg/dL, 2-hour less than 155 mg/dL, and 3-hour less than 140 mg/dL.
What a Gestational Diabetes Diagnosis Means
Gestational diabetes is a condition characterized by high blood sugar levels that develop during pregnancy. It typically arises because pregnancy hormones can lead to insulin resistance, making it harder for the body to use insulin effectively.
A diagnosis of gestational diabetes usually means the condition is temporary and resolves after the baby is born. Proper management during pregnancy is important to promote healthy outcomes for both the pregnant individual and the baby. Unmanaged gestational diabetes can lead to complications such as the baby growing larger than average, which may increase the likelihood of a cesarean section or issues during birth, and a higher risk of neonatal hypoglycemia for the baby after birth. Close monitoring by healthcare providers helps mitigate these potential risks.
Managing Gestational Diabetes
Managing gestational diabetes primarily involves lifestyle adjustments aimed at stabilizing blood sugar levels. A balanced eating plan is a cornerstone of management, emphasizing complex carbohydrates, lean proteins, and healthy fats, while limiting simple sugars. Your healthcare team, including a dietitian, can help create a personalized meal plan to ensure adequate nutrition while controlling glucose levels.
Regular physical activity also plays a significant role, as it helps the body utilize glucose more effectively and can lower blood sugar. Aiming for about 30 minutes of moderate activity most days of the week is a common recommendation, but exercise plans should be discussed with a healthcare provider. Consistent blood sugar monitoring at home provides valuable data to track progress and guide treatment adjustments. If dietary changes and exercise are not sufficient to maintain target blood glucose levels, medication such as insulin injections may be prescribed.