The Incretin Effect in Patients With Gestational Diabetes Mellitus

Observational Study to Evaluate the Reduced Incretin Effect Observed in Patients With GDM in Relation to Reversibility After a Delivery.

The aim of this study is to evaluate the reduced incretin effect observed in patients with T2DM in relation to reversibility. The incretin effect will be measured by means of OGTT and iIVGTT in 12 women with GDM during pregnancy (third trimester), and again 2-3 months post partum. It is anticipated that the incretin effect in patients with GDM is reduced - like in patients with other forms of DM. The investigators estimate that approximately 90 % of the patients with GDM re-establish a NGT 2-3 months post partum. This particular group of patients provides a unique possibility for demonstrating the reversibility of the reduced incretin effect in relation to optimal glycaemic control.

Inclusion Criteria:

• age above 18 years old
• GDM diagnosed according to WHO guidelines (GDM group) or ruled out by OGTT 75g (Control group)

Exclusion Criteria:

• Previous diagnosis of DM
• Positive GAD-65-autoantibodies and/or positive islet cell autoantibodies (ICA)
• Affected biochemical liver parameters (ALAT > 2 times normal upper range)
• Affected biochemical kidney parameters (se-creatinine > 130 µM)
• Treatment with medicine interacting with insulin secretion (e.g. steroids)
• Treatment with medicine that can not be paused for 16 hours