Gestational Diabetes Mellitus: Is It Time to Reconsider the Diagnostic Criteria?

Abstract

It has been 10 years since results from the landmark Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study were published (1) and 8 years since the recommendations of the International Association of Diabetes and Pregnancy Study Groups (IADPSG) appeared in this journal (2). The HAPO study demonstrated a continuous relationship between glucose levels on a 75-g oral glucose tolerance test (GTT) and the risks for selected fetal outcomes. Potential diagnostic criteria for gestational diabetes mellitus (GDM) were considered by a Consensus Panel of the IADPSG, which, after a close vote, decided to select an odds ratio (OR) of 1.75, relative to the mean, for selected outcomes. This corresponded to glucose levels of ≥5.1 mmol/L at fasting, ≥10.0 mmol/L at 1 h, and ≥8.5 mmol/L at 2 h on a 75-g GTT. Although the prevalence of GDM varied markedly between the 15 study centers when applying these criteria, the relationship between glucose and outcomes was consistent, and therefore it was considered appropriate for these criteria to be applied globally (3). The IADPSG recommendations were initially generally greeted with enthusiasm. Finally, diagnostic criteria based on fetal outcomes were available and would replace criteria in the U.S., for example, that were derived from the prediction of subsequent maternal diabetes. Furthermore, given the ethnic diversity of the HAPO participating centers, there was a realistic prospect that their universal adoption was both feasible and practical. However, in the same issue of Diabetes Care that the IADPSG recommendations appeared in there was also a commentary (4) that asked whether the new criteria represented a “problem solved or a …