[Cerebral blood flow during labor].
The successful results obtained using Doppler sonography for antepartal diagnosis gave cause to use the method during labor. For this purpose doppler measurements of the intern fetal carotid artery of a group of 7 patients with normal course of pregnancy were made and a continuous direct CTG was recorded simultaneously. The Doppler parameter, the S/D-ratio, for the contraction phases were compared with those of the contraction--free phases. During the contraction phase the S/D-ratio was higher than during the relaxation period of the uterus. The difference between these values were proved to be statistically significant. A comparison of the doppler parameter of the patients at onset of labor and the patients at the end of labor showed, that the S/D-ratio increased significantly at the end of labor. This result demonstrates, that the intravascular resistance in the fetal carotid artery increased due to the cephalic pressure.