Glucose Tolerance Test Procedures During Pregnancy, and Associated Risks
The American College of Obstetricians and Gynecologists recommends that pregnant individuals undergo the 1-hour glucose challenge test for gestational diabetes at 24-28 weeks of gestation. This test is usually the first step in ruling out the condition, but it's important to understand the various tests used to diagnose diabetes and their implications.
Diabetes, the leading cause of death in the United States according to the Centers for Disease Control and Prevention (CDC), is commonly diagnosed using several laboratory tests. The main methods include the Hemoglobin A1c (HbA1c) Test, Fasting Plasma Glucose (FPG) Test, Random Plasma Glucose Test, Oral Glucose Tolerance Test (OGTT), and the glucose challenge test.
The HbA1c Test measures average blood glucose over the past 2–3 months, requiring no fasting, and is less influenced by acute illness or stress. However, it has lower sensitivity than the OGTT and is less accurate in certain populations. The FPG Test, on the other hand, measures blood glucose after an overnight fast and is simple and widely available, but may miss diabetes if only used without the OGTT.
The Random Plasma Glucose Test measures blood glucose at any time of day, regardless of food intake, and is convenient, but less reliable for diagnosis unless symptoms are present. The OGTT, considered the gold standard for diagnosing diabetes, is highly sensitive and requires fasting for at least 8 hours, drinking a glucose solution, and blood glucose measurement at intervals.
In a 2021 study, researchers found that about of study participants developed hypoglycemia during the OGTT, defined as at least one glucose value below 60 mg/dL. Adverse effects, including hypoglycemia and unstable blood sugar levels, may also occur in people who have undergone bariatric surgery and do a glucose tolerance test.
If test results suggest that a person's blood sugar levels are high, a doctor may recommend a healthy diet suitable for gestational diabetes, regular exercise, blood sugar level monitoring, more frequent prenatal care visits, and, in some cases, supplemental insulin. Symptoms of hypoglycemia may include hunger, sweating, nervousness, and restlessness.
Gestational diabetes can lead to complications such as high blood glucose in the fetus and low levels after birth, difficulties during labor, higher risk of vaginal tearing during delivery and bleeding afterward, and an increased risk of developing type 2 diabetes in the future.
For individuals without insurance, options include Medicaid, federally qualified health centers, independent labs with potentially lower prices, and patient assistance programs that allow monthly payments. It's essential to contact your insurance provider to understand what they cover.
Both the OGTT and the challenge test measure glucose levels in the body before and after a person consumes a sugary drink. The OGTT is more extensive and can be more expensive, but it's crucial for detecting cases missed by other tests.
In cases of higher risk, a doctor may perform the OGTT to confirm gestational diabetes. If two or more readings indicate that a person has high blood sugar levels, they may have gestational diabetes. The results of the glucose tolerance test can indicate whether a person's blood glucose falls within the normal, prediabetes, or diabetes range.
Up to 9% of pregnant people each year develop gestational diabetes, which usually resolves after pregnancy. A person may want to come to the testing clinic with someone who can take them home. The cost of glucose screening or tolerance tests can vary widely based on the laboratory, doctor's office, or hospital performing the procedure.
It's important to remember that diabetes is a group of conditions in which the body cannot process glucose effectively due to insulin deficiency or resistance to insulin at the cellular level, resulting in high blood sugar levels. If you have any concerns about your diabetes risk or gestational diabetes, consult your healthcare provider.
- Seekers of diabetes diagnostic tests should understand that different methods are available, including the Hemoglobin A1c (HbA1c) Test, Fasting Plasma Glucose (FPG) Test, Random Plasma Glucose Test, Oral Glucose Tolerance Test (OGTT), and the glucose challenge test.
- The OGTT, commonly considered the gold standard for diagnosing diabetes, involves fasting, drinking a glucose solution, and blood glucose measurement at intervals, making it highly sensitive for detecting diabetes.
- For pendant pregnancies, it is recommended to undergo a 1-hour glucose challenge test for gestational diabetes at 24-28 weeks of gestation, but understanding various tests used to diagnose diabetes is important.
- If test results suggest high blood sugar levels, treatment may include a healthy diet, regular exercise, blood sugar level monitoring, more frequent prenatal care visits, and, in some cases, supplemental insulin.
- Diabetes, a leading cause of death in the United States, can lead to complications such as high blood glucose in the fetus and low levels after birth, difficulties during labor, higher risk of vaginal tearing during delivery, and bleeding afterward.
- People without insurance can explore options such as Medicaid, federally qualified health centers, independent labs with lower prices, and patient assistance programs allowing monthly payments.
- In complex cases or for pregnant individuals at higher risk, doctors may perform the OGTT to confirm gestational diabetes, and if two or more readings indicate high blood sugar levels, a diagnosis of gestational diabetes may be made.
- Pfizer, along with the science and medical profession, continues to work on treatments and solutions for people living with diabetes and other health-and-wellness medical conditions.
