http://repub.eur.nl/res/aut/27624/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/22313/ 1996-02-14T00:00:00Z In this thesis the following questions were addressed: 1. Are changes in placental vascular resistance associated with alterations in arterial down stream impedance at fetal level? To this purpose placental embolization was carried-out in the fetal lamb with subsequent Doppler velocimetry in the fetal descending aorta (chapter 2). 2. What happens to the human fetal cerebral circulation relative to normal and raised umbilical placental resistance? To answer this question, the human fetal cerebral and umbilical artery were studied under physiological (chapter 3) and pathological conditions (chapter 4) using traditional 2-D real-time and Doppler techniques as well as colour-coded Doppler. 3. Which internal and external variables affect the human fetal cerebral circulation? Here, distinction should be made between breathing movements (chapter 3), behavioural states (chapter 5) and maternal drug administration, with emphasis on indomethacin (chapter 6).