A previous diagnosis of gestational diabetes (GDM) carries a lifetime risk of progression to type 2 diabetes of up to 60%. Identification of those women at higher risk of progression to diabetes allows the timely introduction of measures to delay or prevent diabetes onset. However, there is a large degree of variability in the literature with regard to the proportion of women with a history of GDM who go on to develop diabetes. Heterogeneity between cohorts with regard to diagnostic criteria used, duration of follow-up, and the characteristics of the study population limit the ability to make meaningful comparisons across studies. As the new International Association for Diabetes in Pregnancy Study Group criteria are increasingly adopted worldwide, the prevalence of GDM is set to increase by two-to three-fold. Here, we review the literature to examine the evolution of diagnostic criteria for GDM, the implications of changing criteria on the proportion of women with previous GDM progressing to diabetes, and how the use of different diagnostic criteria may influence the development of appropriate follow-up strategies.
Keywords: Diagnostic oral glucose tolerance test criteria; Gestational diabetes; Impaired glucose tolerance; Pregnancy; Type 2 diabetes.