Screening for dysglycaemia during pregnancy: Proposals conciliating International Association of Diabetes and Pregnancy Study Group (IADPSG) and US National Institutes of Health (NIH) panels

Abstract

The International Association of Diabetes and Pregnancy Study Group (IADPSG) has proposed that blood glucose levels for the diagnosis of gestational diabetes mellitus (GDM) be the values associated with a 1.75-fold increase in the risk of neonatal complications in the Hyperglycaemia and Adverse Pregnancy Outcomes (HAPO) study. However, this recommendation was not adopted by the US National Institutes of Health (NIH) panel as it would have been responsible for a huge increase in the prevalence of GDM with no clear evidence of a reduction of events at such blood glucose values. Considering this aspect, we now propose the use of a blood glucose threshold combination associated with an odds-ratio of 2.0 for neonatal disorders [fasting plasma glucose (FPG)≥95mg/dL, or a 1-h glucose value after a 75-g oral glucose tolerance test (OGTT)≥191mg/dL or a 2-h glucose value≥162mg/dL] for GDM diagnosis. This would lead to a lower prevalence of GDM and concentrate medical resources on those with the highest risk of complications. This would also allow the use of a similar FPG value for both the diagnosis and therapeutic target of GDM. The IADPSG also proposed screening for dysglycaemia during early pregnancy, using FPG measurement with a similar threshold after 24 weeks of gestation. We propose the same strategy considering an FPG value≥95mg/dL as abnormal, but only after confirmatory measurements. We also believe that an OGTT should not be used before 24 weeks of gestation as normal values during that time are as yet unknown.