Background: Women with a history of GDM have a 10-fold increased risk of developing type 2 diabetes (T2D) compared with women without GDM. The rate of conversion to diabetes varies from 2 to 12.5% at 1 year. To date, Italian guidelines do not recommend screening one year after delivery. Aim: To evaluate any glycaemic changes 1 year after delivery in women with a history of GDM. Methods: 77 women were followed up 6-12 weeks and 1 year after delivery (37±5 yrs, 83.1% Caucasian ethnicity, 36.4% were treated with insulin). The 2h-OGTT and the questionnaires on adherence to the Mediterranean diet (PREDIMED) and physical activity (IPAQ) were performed. Results: the women were of normal weight (BMI: 24.5±5.2 vs 24.2±5.9 kg/m2, p=0.96) both at baseline and at 1 year, with a waist circumference >80 cm (87.7±13.4 vs 82.7±13.8 cm, p=0.04). Dietary adherence was adequate (7.6±1.4 vs 7.7±1.8, p=0.82), whereas the IPAQ score decreased (586±125 vs 496±223 Mets, p=0.13). At baseline, 22.1% showed AGT (IFG, IGT and both), 5.2% T2D and 72.7% NGT. At 1 year after delivery, 36.5% had AGT, 6.5% T2D and 57% NGT. 19 women with NGT at baseline showed a worsening of blood glucose levels (73.7% with IFG, 15.8% with IGT, 10.5% with IFG and IGT). These women were overweight (BMI: 25.9±7.0 vs 26.5±8.8 kg/m2, p=0.83) and gaining weight (68.8±18.5 vs 70.2±18.9 kg, p=0.78) and were not physically active. Furthermore, waist circumference at 1 year after delivery was associated with worsening glycaemic control [90.1±18.6 cm, OR 1.06 (1.0-1.1), p=0.01] after adjustment for age and ethnicity. Conclusion: The development of glycaemic alterations or diabetes in these women increases over time with 43% of women showing glycaemic changes already at 1 year follow-up. It is important to re-evaluate these women with more intensive follow-up and to recommend lifestyle modifications in order to reduce weight gain, visceral fat storage and worsening of the glycometabolic profile and cardiovascular risk.