Metformin Versus Insulin in Gestational Diabetes

Metformin Versus Insulin in Gestational Diabetes. A Randomized Controlled Single Center Trial.

Gestational diabetes is traditionally treated with insulin. Metformin is a peroral drug used worldwide in the treatment of type 2 diabetes and also in a few studies on patients with gestational diabetes. The investigators aim is to compare insulin and metformin in the treatment of gestational diabetes. The investigators hypothesis is that there is no difference between insulin and metformin treated mothers in the main outcome criteria (birth weight, neonatal complications).

Gestational diabetes is traditionally treated with insulin. Metformin is a peroral drug used worldwide in the treatment of type 2 diabetes and also in a few studies on patients with gestational diabetes. The investigators aim is to compare insulin and metformin in the treatment of gestational diabetes. The investigators hypothesis is that there is no difference between insulin and metformin treated mothers in the main outcome criteria (birth weight, neonatal complications). The study was performed as a randomized controlled trial in one center, Turku University hospital using the non-inferiority design in June 2006 - December 2010. The final study population consisted of altogether 217 women, of whom 110 received metformin and 107 insulin.

Inclusion Criteria:

• Mothers with gestational diabetes who had at least twice plasma glucose at fasting > 5.4 mmol/L and/or 1 hour postprandial value > 7.7 mmol/L at 24 to 32 gestational weeks

Exclusion Criteria:

1. Fasting glucose > 7.0 mmol/L or 1 hour postprandial plasma glucose > 11.0 mmol/L or Glycosylated hemoglobin A1c (HbA1c) > 7.0%
2. Renal, hepatic or cardiac failure
3. Pregestational use of metformin
4. Pregnancy with multiple fetuses