A pregnant female presented with a family history of diabetes. Her glucose tolerance test (GTT) is positive. All of the following are TRUE about GTT, EXCEPT:
**Core Concept**
The glucose tolerance test (GTT) is a diagnostic tool used to assess the body's ability to regulate blood glucose levels after a glucose load. It is commonly used to screen for gestational diabetes mellitus (GDM) in pregnant women.
**Why the Correct Answer is Right**
During a GTT, a patient is given a glucose solution to drink, and blood samples are collected at intervals to measure the glucose levels. A positive GTT result indicates impaired glucose tolerance, which can lead to GDM. The test is usually performed between 24 and 28 weeks of gestation. In GDM, the body is unable to produce enough insulin to compensate for the increased demand, leading to hyperglycemia.
**Why Each Wrong Option is Incorrect**
**Option A:** This statement is incorrect because GTT is a diagnostic test for impaired glucose tolerance and is not a screening test for type 1 diabetes.
**Option B:** This statement is incorrect because GTT is performed in a fasting state, followed by the ingestion of a glucose solution.
**Option C:** This statement is incorrect because the GTT is usually performed between 24 and 28 weeks of gestation, not immediately after conception.
**Clinical Pearl / High-Yield Fact**
The World Health Organization (WHO) recommends that all pregnant women undergo a 75-g oral glucose tolerance test (OGTT) between 24 and 28 weeks of gestation to screen for GDM.
**Correct Answer:** A.