Final answer:
Gestational diabetes screening should be performed during the 24th to 28th weeks of pregnancy. A glucose tolerance test (GTT) is typically done to diagnose gestational diabetes.
Step-by-step explanation:
It is recommended to check for gestational diabetes between weeks 24 and 28 of pregnancy. This is due to the fact that the body needs twice as much glucose during the third trimester of pregnancy, which can result in ketoacidosis and an excess of ketone bodies being produced. Usually, a glucose tolerance test (GTT) is performed to identify gestational diabetes. When a patient does not exhibit glucosuria but is suspected of having diabetes mellitus, a GTT is performed. It is also performed when the blood glucose level is almost normal.