Pre-analytical diagnostic differences despite high adherence to guidelines for gestational diabetes mellitus.

Regional variations in the prevalence of gestational diabetes mellitus (GDM) have been found across Denmark. The objectives of this exploratory survey were to evaluate adherence to the national guideline for screening and diagnosing GDM and to identify variations in pre-analytical or analytical factors, which could potentially contribute to variations in GDM prevalence across regions. In a national interview-based survey, obstetric departments and laboratories throughout Denmark handling GDM screening or diagnostic testing were invited to participate.