Screening for gestational diabetes; past, present and future

AbstractGestational diabetes is carbohydrate intolerance, with onset or first recognition of hyperglycaemia during pregnancy. Several studies have suggested that gestational hyperglycaemia is associated with adverse maternal and fetal outcomes, promoting the case for screening. Conversely, others argue that screening for gestational diabetes may colour the clinical judgement, influencing further management, e.g. more ‘unjustified’ caesarean sections. Additionally, the lack of definitive data either on a clear‐cut glycaemic threshold for the development of adverse outcomes or on the impact of intervention is emphasized by opponents of screening. This review attempts to evaluate the available data on screening for gestational diabetes. Oral glucose tolerance test is promoted on the basis that the diabetogenic stress of pregnancy is encountered during late gestation and is best recognized in the fed state. There are different tests, including the 1 h/50‐g, 2 h/75‐g and 3 h/100‐g tests, with practical limitations, including the time and cost involved and the unpleasant supra‐physiological glucose load that is unrelated to body weight, and issues of reproducibility and sensitivity/speci