1 hour glucose tolerance test - pregnancy normal range
Searched over 200M research papers
Summary
10 papers analyzed
These studies suggest that the normal range for a 1-hour glucose tolerance test in pregnancy is not clearly defined and may vary based on gestational age and other factors.
Not a yes or no question
To use the Consensus Meter, try asking a simple yes or no question
Research summarized with Copilot
Beta19 papers analyzed
Normal Range for 1-Hour Glucose Tolerance Test During Pregnancy
Introduction to Glucose Tolerance Testing in Pregnancy
Gestational diabetes mellitus (GDM) is a condition characterized by glucose intolerance that is first recognized during pregnancy. The 1-hour glucose tolerance test (GTT) is a common screening tool used to identify women at risk for GDM. This test involves administering a 50-gram glucose load and measuring blood glucose levels one hour later. Understanding the normal range for this test is crucial for early detection and management of GDM.
Normal Range for 1-Hour Glucose Tolerance Test
The normal range for the 1-hour glucose tolerance test during pregnancy is typically considered to be less than 140 mg/dL. Values above this threshold may indicate the need for further testing, such as the 3-hour 100-gram oral glucose tolerance test (OGTT), to confirm a diagnosis of GDM .
Implications of Abnormal 1-Hour GTT Results
Increased Risk of Adverse Pregnancy Outcomes
Women with a 1-hour glucose challenge test (GCT) result of 200 mg/dL or higher are at a significantly increased risk for adverse pregnancy outcomes, including preeclampsia and shoulder dystocia, compared to those with lower GCT results. Additionally, even a single abnormal value on the 3-hour OGTT is associated with increased risks of macrosomia, large for gestational age infants, neonatal hypoglycemia, and cesarean delivery.
Reproducibility and Variability of GTT Results
The reproducibility of the 3-hour OGTT can be inconsistent, with approximately 24% of pregnant women showing non-reproducible results. Factors such as maternal stress, indicated by increased norepinephrine levels, may contribute to these variations.
Long-Term Health Implications
Hypertension and Cardiovascular Risk
The shape and values of the glucose curve during the OGTT can help identify women at risk for developing hypertension later in life. A monophasic response (a peak at 1 hour followed by a decline) is associated with a higher risk of elevated blood pressure and hypertension compared to a biphasic response.
Low Birth Weight Risk
Interestingly, women with normal glucose tolerance but low glycemic values during the OGTT are at a higher risk of delivering low birth weight infants. This risk remains significant even after adjusting for factors such as body mass index (BMI) and gestational weight gain.
Conclusion
The 1-hour glucose tolerance test is a critical tool in the early detection of gestational diabetes mellitus. A normal range is typically considered to be less than 140 mg/dL, with values above this threshold warranting further testing. Abnormal results are associated with increased risks of adverse pregnancy outcomes and long-term health implications for both the mother and child. Understanding these risks underscores the importance of accurate screening and timely intervention in managing gestational diabetes.
Sources and full results
Most relevant research papers on this topic
