Quantitative studies on fetal actocardiogram.

AIM: To quantitatively analyze actocardiography as a method to differentiate between active and resting fetal states.

METHODS

We established five new quantitative parameters for actocardiogram; they include duration, occupancy, and frequency of movement bursts, and fetal heart rate acceleration to movement ratio (A/B ratio) in duration and number. These parameters were analyzed and compared in 14 normal late pregnancies and in non-hypoxic sinus bradycardia due to fetal cardiac sick sinus syndrome (n=1), hypoxic non-reactive non-stress test (n=3), hypoxic fetal distress (n=1), and that ensuing in death (n=1).

RESULTS

Fetal hypoxic disorders differed from non-hypoxic states in the significant reductions of burst frequency (normal pregnancy mean was 0.65-/+0.22 cpm and fetal distress 0.24 cpm), occupancy (32.67% and 10.00%, respectively), and the ratio of durations of acceleration to movement burst (1.03 and 0, respectively).

CONCLUSION

Our study of quantitative actocardiogram parameters in normal pregnancy and various hypoxic fetal disorders demonstrated new characteristics of fetal movement and its relation to fetal heart rate. The results are promising for further analysis of fetal behavior and abnormalities.