In diabetic patients, the correlation between glycosilated adult hemoglobin (HbA1c) levels and average glucose concentration over the preceding weeks is well known. We have, therefore, sought the possibility to identify newborns at risk measuring cord blood levels of fetal glycosilated hemoglobin (HbF1) in neonates of diabetic mothers. HbF1 was tested by the isoelectrofocusing method. Mean values of HbF1 have been proven to be higher in in infants born to diabetic mothers as compared to normal newborns. The highest levels were encountered in those babies whose mothers had shown a poor glycemic control during the last few weeks of pregnancy.