Evaluation of an impedance measurement technique for uterine contraction recording

An electronic system for the detection of uterine contractions by impedance measurement was evaluated in 30 subjects during the first stage of labor. The advantage of the system was patient comfort and ease of application of the recording electrodes. Simultaneous recordings of uterine contraction activity with conventional extra- or intra-uterine recording systems were made. The available evidence from this study indicated that 82 to 84% of the uterine contractions were accurately detected and that the onset and end of each uterine contraction is a reliable parameter of impedance measurement.