To evaluate, in pregnant women at high risk for gestational diabetes (GDM), the longitudinal changes of adiponectin, carbohydrate and lipid metabolism, and to assess their independent value as risk factors for the development of GDM. Fifty women at beginning of pregnancy were studied. Adiponectin, insulin sensitivity (homeostasis model assessment, HOMA) and lipid panel were measured at 1st, 2nd and 3rd trimesters of pregnancy. Twelve patients developed GDM. In both groups, GDM and normal glucose tolerance (NGT), adiponectin decreased from 1st to 2nd and 3rd trimesters by about 5 and 20% (GDM, p < 0.05), and of about 17 and 25% in NGT (p < 0.05), respectively. Values observed in NGT were similar to those of GDM (F = 9.401; p = 0.238). The Cox regression model identified as the strongest independent risk factor for GDM HOMA over 1.24 (RR = 14.12) at 1st trimester, fasting glycaemia over 87 mg/dl (RR = 42.68) triglycerides over 158 mg/dl (RR = 5.87) and body mass index (BMI) over 27 kg/m(2) (RR = 4.38) at 2nd trimester. Adiponectin in high-risk women is characterised by a constant reduction throughout gestation, irrespective of the development of GDM. HOMA, fasting glycaemia, triglycerides and BMI, but not adiponectin are independent predictors of GDM.