Définitions, épidémiologie, facteurs de risque

Gestational diabetes mellitus is defined as carbohydrate intolerance that begins or is first recognized during pregnancy. Its prevalence, generally situated between 2-6%, may reach 10-20% in high-risk populations, with an increasing trend across most racial/ethnic groups studied. Among classical risk factors, previous gestational diabetes, older maternal age and obesity have the most important impact on gestational diabetes risk. Racial/ethnic origin and family history of type 2 diabetes have a significant but moderate impact (exept for type 2 diabetes in siblings). Several non classical factors have been recently characterized, either physiological (low birth weight and short maternal height) or pathological (polycystic ovaries). The multiplicity of risk factors and their interactions results in a low reliability of risk prediction on an individual basis.