STUDY ON THE DEVELOPMENT OF DOPPLER PARAM ETERS IN FETAL AND MATERNALVESSELS 10 DAYS BEFORE TO 10 DAYS AFTER SCHEDULED DATE OF PARTURITION

Doppler sonography can help to assess a foetal risk situation prospect ively. This procedure is therefore well suited for the screening of ri sk pregnancies in the 3rd trimenon. The role of Doppler ultrasound at delivery is still controversial, since, on the one hand, no data on th e behaviour of Doppler parameters directly at the onset of delivery ar e available, and on the other hand the obstetric consequences from pat hological findings are not clear. For this reason, we observed 45 norm al pregnancies from the 10th day prior to the date of confinement till the 10th day post partum. In 20 patients we registered Doppler parame ters from 4 days before until the onset of true labour. In all these c ases, a reduction of the end-diastolic blood flow in the foetal aorta was found, which became evident by the increase of the resistance inde x to pathological values. Concomitant decrease of the resistance index in the foetal carotid artery was typical for a circulatory system. Si nce foetal outcome was normal in all newborn, this change in Doppler p arameters directly at the beginning of labour must be considered as ph ysiological. The findings suggest a physiological placental insufficie ncy. Since however, parameters in the uterine vessels did not show any changes, the insufficiency has its probable origin in the placenta. F rom these findings, one might speculate, that the supply deficiency is the labour inducing factor. No clinical consequence can thus result f rom pathological Doppler data found in patients directly prior and aft er delivery. Cardiotocographic screening is necessary. The results of this study show, that there is only a limited indication for Doppler s onography shortly before and after delivery and GTG monitoring seems t o be of greater importance.