Which method is used to confirm gestational diabetes after an initial screening?

The confirmation of gestational diabetes after an initial screening is effectively accomplished using a glucose tolerance test, which can be conducted over a duration of 2 hours or 3 hours. During this test, the patient is given a glucose solution to drink, and blood glucose levels are measured at specific intervals following the ingestion of glucose. This method is considered the gold standard for diagnosing gestational diabetes because it accurately assesses how well the body processes glucose, providing a comprehensive evaluation of insulin resistance that may occur during pregnancy.

The glucose tolerance test captures real-time responses to glucose load, allowing for a more definitive diagnosis than other methods. For instance, while fasting blood tests can indicate hyperglycemia, they do not provide information on how the body manages glucose levels over time, which is crucial for diagnosing gestational diabetes. Other options, such as urine glucose tests and home glucose monitoring, can be helpful for management but are not definitive diagnostic tools for gestational diabetes in the context of confirming a diagnosis after an initial screening. Therefore, the glucose tolerance test remains the most reliable method for this purpose.