Is grand multiparity associated with an increased risk of dysglycaemia?

We sought to determine the risk of diabetes and IGT/IFG with grand multiparity.Women, agedor =25 years, from the Australian Diabetes, Obesity and Lifestyle Study and the Crossroads Undiagnosed Disease Study (a rural study in Victoria, Australia), participated in a household census (response 67 and 70%, respectively), subsequently attending a biomedical examination that included an oral glucose tolerance test (58% [6198] and 69% [819]).After adjusting for age, obesity and socio-economic status, diabetes, but not IGT/IFG, was less common among women with a parity of 1 to 2 (odds ratio [OR]=0.64 [0.48-0.84]) and 3 to 4 (OR=0.72 [0.53-0.96]) than in grand multiparous women. This relationship was unrelated to past hysterectomy, use of the oral contraceptive pill or menopausal status.Grand multiparity is associated with an increased risk of diabetes but not of IGT/IFG. We postulate that parity accelerates transition from IGT/IFG to diabetes, more than it does transition from normal glucose tolerance to IGT/IFG.