During a four-year period we analyzed the significance, sensitivity and sensibility of myoma Doppler flow during pregnancy in relation to the course and outcome of the pregnancy and to later histopathological findings. By following 36 older primigravidas with determined myomas, we observed the course of the pregnancies in all trimesters and analyzed myoma Doppler flow. In conditions where the resistance index showed the possibility of uterine sarcoma, the pregnancy was ended by surgery; not only was myomectomy performed but also complete uterine hysterectomy with the previous consent of the patient. Doppler flow was accepted as the authoritative parameter for non-invasive detection of a malignant process. Considering the obstetrical findings, other patients were delivered vaginally or operatively, but after puerperium they were subjected to control examinations and myomectomy because Doppler flow findings did not show any indications of sarcoma. By histopathological analysis, we received benign results in 31 cases, while in four cases where we decided on hysterectomy and surgical delivery, we received malignant results, i.e. leiomyosarcoma. In four cases of performed hysterectomy immediately after cesarean section, the resistance index (RI) of revascularization within the myoma was in the range between RI 0.30 +/- 0.02. Flows within the uterine artery were 0.54 +/- 0.03.