Laboratory parameters of the 1st order – obligatory laboratory tests.
- Casual blood glucose measurement – if this is ≥ 200 mg/dl (> 11.1 mmol/l), then a fasting blood glucose measurement should be performed
- Fasting blood glucose measurement – if this is ≥ 92 mg/dl (> 5.1 mmol/l), then a second measurement should be performed and then, if necessary, further clarification
- 50 g glucose screening test* (Glucose Challenge Test, GCT) – is performed as standard in the 24th-28th week of pregnancy [gold standard as screening method]Note: The 50 g glucose screening test with limit 135 mg/dl is considered susceptible to interference (time of day, last meal), insufficiently sensitive and specific.
Laboratory parameters 2nd order – depending on the results of the history, physical examination and mandatory laboratory parameters – for differential diagnostic clarification.
- 75 g-oGTT (oral glucose tolerance test; oGTT)* – 50 g-glucose screening test* followed by a conventional oral glucose tolerance test if necessary.
- HbA1c (long-term blood glucose measurement) – an elevated HbA1c level may indicate impending gestational diabetes already in early pregnancy: for every 0.1 percentage point increase in HBA1c, the risk of gestational diabetes increased by 23% (odds ratio 1.23; 95% confidence interval 1.10 to 1.38) ; sensitivity was relatively low depending on the cut-oo point (HbA1c value of 5.7% or 5.1%) was relatively low, with values ranging from 21 to 47%; however, the specificity (probability that actually healthy people who do not suffer from the disease in question are also detected as healthy in the test) was very high at 98%.
- Uringlucose
* Please see “Oral glucose tolerance test (oGTT) in gestational diabetes” for measures to be observed before performing the oGTT.
Further notes
- In the following year, women with gestational diabetes (GDM) have a sevenfold increased risk of diabetes mellitus.
- Fathers have an 18% increased incidence (frequency of new cases) of diabetes mellitus, taking into account age, comorbidities (concomitant diseases), type of living arrangement, ethnic background, and social status.
