[Fetal heart rate accelerations and fetal oxygen pressure sub partu]

By means of tcPO2 measurement, a total of 297 FHR accelerations from 55 oxygen cardiotocograms were analysed with regard to their association with changes in fetal oxygen pressure sub partu. It could be demonstrated that the transcutaneous oxygen pressure of 2.3 kPa (17.1 mmHg) with occasional accelerations was significantly (alpha less than 0.05) higher than that of 2.2 kPa (16.6 mmHg) with periodic accelerations. Oxygen pressure with occasional accelerations with "classical parameters" (amplitude greater than or equal to 15 bpm, duration greater than or equal to 15 sec) did not significantly differ from that with one or both parameters below these minimal values. Furthermore, our results suggest the production of periodic accelerations by pressorreceptor reflex due to intermittent disturbance in umbilico-placental perfusion.