Research was competing with other projects in the department, and no patients were recruited.

A pragmatic, comparative effectiveness trial of glyburide versus metformin.

Patients with gestational diabetes requiring pharmaceutical treatment will be randomized to receive glyburide or metformin. Dose increases will be determined by the patient's physician. Patients will be determined to have failed either medication if glucose control can not be achieved with the maximum dose of the medication, if insulin is stared to achieve glucose control or if another oral agent is started along for glucose control.

Inclusion Criteria:

We will include women between 20 and 34 weeks gestational age, with a diagnosis of GDM as per the following criteria:

• 1 hour Glucose tolerance test of >130 mg/dl, followed by two abnormal values on 3 hour Glucose tolerance test, or:
• A single 1 hour Glucose tolerance test value of > 200 mg/dl, and:
• Failure to achieve glycemic control with diet and exercise or deemed to require pharmacological therapy as per physician's criteria

Exclusion Criteria:

• - Known renal impairment.
• Known hepatic disease.
• Pre-gestational diabetes.
• Known allergy to glyburide, metformin or sulfa drugs.