Whether gestational diabetes mellitus (GDM) screening and management by different criteria and in different settings is cost-effective has been debated for more than a decade. A 2009 report from The Lancet’s Stillbirth Series steering committee put detection and management of GDM on a priority list of interventions to reduce stillbirth, 1 and the potential key role of GDM on the long-term health of the mother and her offspring is being discussed at the highest political level in the United Nations (UN) General Assembly and other UN bodies. 2 4 The suggestion of new screening criteria by the International Association of Diabetes and Pregnancy Study Groups (IADPSG) 5 in 2010 has added to the debate. These extensive deliberations notwithstanding, we are only beginning to understand which interventions might be effective at reducing the burden of GDM, and at what cost. 6 To institute appropriate policies, decision makers at national and global levels need additional reliable information on the cost and cost-effectiveness of GDM screening and treatment.