The clinical significance of gestational diabetes mellitus, or carbohydrate intolerance with onset or first diagnosis during pregnancy, is a subject of debate.1,2 The concept of gestational diabetes mellitus was popularized before considerations of "evidence-based medicine" came on the scene. Like many other conditions, gestational diabetes mellitus became a clinical entity without the carefully collected epidemiologic data we now require. Nevertheless, the majority of obstetricians in the United States screen their pregnant patients for this condition.3 There is a large body of evidence to support the contention that marked maternal hyperglycemia in the range found in patients with preexisting diabetes mellitus can have an adverse impact on fetal growth, development, and well-being. The mechanism appears to be fetal hyperinsulinemia evoked by hyperglycemia. The following questions need to be resolved: (1) How severe must maternal hyperglycemia be to measurably worsen pregnancy outcome? (2) Can we intervene to prevent adverse outcomes?
Coustan DR. Management of Gestational Diabetes MellitusA Self-fulfilling Prophecy?. JAMA. 1996;275(15):1199-1200. doi:10.1001/jama.1996.03530390065037