Correlation of fetal heart rate patterns with umbilical artery pH and catecholamines during last hour of labor.

Fetal heart rate (FHR) patterns were analysed during last hour of labour and correlated to umbilical artery pH and catecholamine (CA) levels. Fetuses with pathological FHR had significantly higher levels of CA than those with normal FHR. Particulary high levels were found in fetuses with bradycardia and late decelerations. FHR was further analysed by a computer (DPAC, data processor and computer) in 100 women during last hour of labor. No correlation between deceleration areas of variability and umbilical artery pH and CA was found. It is concluded that although there is a good correlation between the general FHR-pattern and umbilical artery CA and pH it is impossible to quantify the degree of fetal distress by calculation of deceleration areas and variability.