[Studies on computer processing of fetal heart beat intervals with the comparison to several analyzing methods...

Fetal heart beat intervals are statistically studied with the use of direct fetal ECG signal, universal counter module, HP 2100 A computer and fetal heart rate meter. In 78 cases of labor, 260 data trains which are composed of 250 beat intervals respectively are utilized for the study. Fetal heart rate curves are classified into Hammacher's 4 oscillation types. Every beat interval (BI), beat interval difference (ID) are studied with the comparison to interval index (II) and differential index (DI) of Yeh, and long term irregularity index (LTI) and short term irregularity index (STI) of de Haan. Among 4 oscillation types, ID value is the least in type 0, the next in type 1 then 2, and the largest in type 3. The differences are significant respectively. Percentages of ID below 1 ms histogram showed the largest value in type 0, the next in type 1 then 2, and the least in type 3. The differences are significant respectively. Normal type 2 and abnormal type 0 cases are compared by STI, DI and ID. Mean value of STI shows no difference between the cases, but the SD is very small in type 0. DI is small in type 0, and mean and SD of ID of the author are small in type 0. The utility of ID is suspected from the results in this study.¿¿¿¿¿¿¿¿¿¿¿¿¿¿¿¿¿¿