Doppler studies of umbilical, uterine and arcuate artery velocity wave forms were performed in 40 insulin-dependent diabetic women in the first and second half of pregnancy. Using a continuous-wave Doppler device, the resistance index (RI) was calculated to determine the degree of vascular resistance in utero-placental and foeto-placental compartment. The 90th percentile was used to classify flow velocity profiles. In addition, diastolic notching and incomplete registration of uterine and arcuate arteries were considered as an abnormal result in utero-placental perfusion. The prevalence of abnormal velocity wave forms in this risk group was higher than in a non-diabetic population. No significant correlation was found between abnormal Doppler studies and White's classification. Patients with vasculopathy represent a high-risk group for foetal growth retardation, which may be detected early by umbilical and especially uterine artery Doppler studies. Abnormal uterine and arcuate artery wave forms allowed identification of patients who developed pregnancy-induced hypertension/preeclampsia.