Effectiveness of Metformin Compared to Insulin in Pregnant Women With Mild Preexisting or Early Gestational Diabetes

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.

Conditions

• Non Insulin Dependent Diabetes
• Pregnancy

Interventions

DRUG

Metformin

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.

DRUG

Insulin

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.

Sponsors & Collaborators

• WakeMed Health and Hospitals

  collaborator OTHER

• University of North Carolina, Chapel Hill

  lead OTHER

Principal Investigators

• Ashley Hickman, MD · University of North Carolina, Chapel Hill

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2008-08-31

Primary Completion

2010-02-28

Completion

2010-04-30

Countries

• United States

Study Locations