Effectiveness of Metformin Compared to Insulin in Pregnant Women With Mild Preexisting or Early Gestational Diabetes
Condition: Non Insulin Dependent Diabetes; Pregnancy
MeSH terms: Diabetes Mellitus, Type 2
Intervention: Metformin; Insulin
Intervention description: Women randomized to the Experimental arm will receive standard diet and glucose self-monitoring education. They will be initiated on Metformin 500 BID if they were medication naïve, or will be continued on their current dosage of Metformin if they were taking it prior to pregnancy. At each clinic visit fasting and one hour post prandial glucose values will be reviewed, and dosage will be titrated to a maximum of 2250mg/day to achieve target glycemic control. If glycemic control can not be achieved with Metformin as a single agent insulin will be added.; Women randomized to the Insulin group will receive standard diet and glycemic monitoring education. They will be initiated on weight based Regular and NPH insulin at a total dosage of 0.7units/kg in the first trimester or 0.8units/kg in the second trimester divided as 2/3 of the total dosage (with 2/3 given as NPH and 1/3 given as Regular) administered before breakfast and 1/3 of the total dosage (with 1/2 given as NPH and 1/2 given as Regular)administered with dinner. At each clinic visit fasting and one hour post prandial glucose values will be reviewed, and dosage will be titrated to achieve optimal glycemic control with fasting values <90 and one hour post prandial values <130.
Intervention MeSH terms: Insulin; Insulin, Globin Zinc; Metformin; Insulin, Isophane; Isophane Insulin, Human
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Enrollment: 31.0
Sex: Female
Minimum age: 18 Years
Healthy volunteers: No
Keywords: Non Insulin Dependent Diabetes; Pregnancy

Summary:

      Many women come into pregnancy with diabetes that is controlled with either Metformin or diet
      control; however, the current standard of care for the treatment of preexisting diabetes in
      pregnancy is insulin. Metformin is widely used in the non-pregnant population for glycemic
      control, and has been used in pregnancy for other indications without adverse maternal or
      fetal outcomes. What remains unproven is the ability of Metformin to adequately control
      glucose in women during pregnancy.

      Our goal is to randomize 100 women who enter pregnancy with diabetes that is controlled by
      either diet or an oral agent and women who are found to have an abnormal glucose challenge
      test at less than 20 weeks to either standard treatment with weight based Regular and neutral
      protamine Hagedorn (NPH) insulin or Metformin. Our hypothesis is that Metformin will provide
      glycemic control that is equivalent to insulin in these women.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Receiving prenatal care at University of North Carolina (UNC), Chapel Hill Obstetric
             clinics and planning delivery at UNC Women's Hospital

          -  Diagnosis of Diabetes prior to pregnancy with use of an oral hypoglycemic agent or
             dietary control

          -  Diagnosis of early gestational diabetes prior to 20 weeks gestation via abnormal 3
             hour glucose challenge testing using the national diabetes data group (NDDG)criteria

          -  Less than 24 weeks at study enrollment

          -  Singleton or twin pregnancy

          -  English or Spanish speaking

          -  Able to give informed consent

        Exclusion Criteria:

          -  End organ complications of diabetes (retinopathy, renal insufficiency, etc.)

          -  Prior need for insulin for glycemic control

          -  History of diabetic ketoacidosis (DKA) or hyperosmolar state

          -  Prior adverse reaction (ie. lactic acidosis) or allergy to Metformin

          -  Kidney or liver disease

          -  Significant medical co-morbidities (lupus, cystic fibrosis, etc.) Hypertension
             controlled on one medication, well controlled asthma, and well controlled thyroid
             disease are not excluded.