Characterization of Uterine Response to Misoprostol based on Electrohysterogram

When the maternal and fetal risks of prolonging gestation are higher than the benefits, labor induction is performed in order to stimulate uterine contractions and to facilitate cervical ripening. Nevertheless, not all cases end up in successful induction leading to an increase in the rate of caesarean sections. The aim of this study was to study the electrophysiological uterine response to misoprostol drug by obtaining and analyzing the evolution of temporal and spectral parameters from uterine electromyogram (electrohysterogram, EHG) records picked up during the first 4 hours of labor induction. Successful inductions showed a progressive increase in amplitude and a frequency shift in spectral content towards higher frequencies approximately 120 min after the initiation of labor induction; such response was not seen in failed inductions. In conclusion, the electrophysiological response caused by effect of misoprostol in pregnant women has been characterized by EHG parameters which showed patterns in their evolution that were different for successful and failed labor inductions. EHG recording and analysis could serve as a very helpful tool to predict the success of labor induction and hence reduce risks and facilitate labor management in this frequent clinical situation.