Statistical approach to analysis of electrohysterographic signal

The intensity of contraction of the pregnant uterus expressed by intrauterine pressure depends on the quantity of contractile cells being activated at a time. Their electrical activity creates differences of potentials known as electrohysterogram (EHG). The abdominal electrohysterogram can be an alternative to the tocography tool, which is useful in clinical evaluation of the pregnant uterus activity. We describe a procedure for analysis of EHG signal. It performs the running estimation of the ratio of standard deviation to mean value in the signal provided and semi-automatically detects segments of signal corresponding to periods of increased uterine activity. The power carried by the signal in specified frequency band is estimated, which enables power spectrum density tracking for consecutive contractions.