[A study on the correlation between automated fetal heart rate analysis and changes in umbilical cord arterial blood].

A correlation between various parameters of automated analysis of fetal heart rate (FHR) and blood gases of umbilical cord artery examined immediately after vaginal delivery was investigated in 71 cases by external monitoring and 61 cases by internal monitoring. Parameters of automated analysis including FHR score, fetal distress (FD) index, uterine contraction area value and number of accelerations were determined every 5 minutes by using microcomputer-aided automatic analysis of FHR. Almost all of these neonates showed a high Apgar score of 8 or more except for 7 infants. However, parameters of automated FHR analysis of 15 or 20 minutes before delivery were well correlated with umbilical cord arterial BE and HCO3- in the externally monitored group. The maximum correlation coefficients were noted between FHR score and BE(r = -0.375), FD index and BE (r = -0.393) 20 minutes before delivery, FD index and HCO3- (r = -0.401) and FHR score and HCO3- (r = -0.393) 15 minutes before delivery. The uterine contraction area value was well correlated with BE and HCO3- of umbilical cord blood 10 minutes before the maximum correlation of FD index and FHR score was observed. In the internally monitored group, FHR parameters were well correlated with BE and HCO3- 35 minutes before delivery.