Differenzialdiagnostik des gestationsdiabetes: Welches risiko besteht für einen typ-1- oder typ-2- diabetes nach der schwangerschaft?

The incidence rates of gestational diabetes (GDM) are increasing worldwide, similar to that of type 2 diabetes. This is mainly due to the increasing body weight during pregnancy which can shift physiological gestational insulin resistance towards a pathological range. After the diagnosis of GDM is made, it is relatively easy to assess the risk for type 2 or type 1 diabetes postpartum by using clinical and biochemical markers. The German GDM multicenter study shows that about 10% of women with GDM have antibodies against either glutamatdecarboxylase (GAD), or islet-antigen 2 (IA-2), or both. Predominantly lean patients who have to be treated with insulin during pregnancy are much more likely to be islet antibody positive and are at a very high risk of developing type 1 diabetes within the first year postpartum. The prevalence of MODY (maturity diabetes of the young) cases diagnosed during pregnancy is estimated to be less than 5%. A positive family history of diabetes, persisting fasting hyperglycemia postpartum, or a rather moderate increase of glucose during the OGTT using 75 g glucose can point to the diagnosis of MODY. If the risk of diabetes postpartum is considered to be high, women with GDM should undergo an OGTT immediately after birth and then at least every two years. Data from the Diabetes Prevention Program (DPP) subgroup analysis of individuals with former GDM and impaired glucose tolerance show that prevention of diabetes by both life style intervention and Metformin is highly effective.