Objectives: To study the impact of pregestational DM on fetal middle cerebral (MCA) and umbilical arteries (UA) Doppler indices and hence, evaluating their diagnostic performance as predictors for adverse neonatal outcome.  
Methods: The study included 2 equal groups of 60 patients each, thus making up a total of 120 patients; control group of healthy pregnant women and study group included pregnant patients known to have pregestational diabetes. The study group was furtherly subdivided into two equal subgroups of 30 patients each. This sub classification was made according to to HbA1C levels namely; controlled diabetics (defined as those having HbA1C < 6.5 %) and uncontrolled diabetics (defined as those having values of HbA1C ≥ 6.5 %). UA, MCA Doppler indices (resistance index and pulsatility index) and Cerebroplacental Doppler ratio were measured for each patient. Neonatal outcome was assessed and recorded following delivery. The following parameters were assessed: neonatal blood sugar, 1min and 5min Apgar score and admission to neonatal intensive care unit.   
Results: The sensitivity and specificity of umbilical artery Doppler in the prediction of adverse neonatal outcomes among diabetic patients were 25% and 88.89%, respectively, while, the sensitivity and specificity of middle cerebral artery Doppler were 20.83% and 91.67%, respectively. The resistance index and pulsatility index of MCA and UA were not of significant corelation with any of the neonatal outcomes (Pearson's r ranged -0.07 to 0.13, p > 0.05).
Conclusion:  maternal DM is not associated with significant abnormalities in Doppler indices of placental or fetal circulation. In addition, both UA and MCA had low sensitivity in the prediction of adverse neonatal outcome.