Continuous monitoring of cervical dilatation and fetal head station during labor.

An ultrasound-based computerized system was developed for monitoring cervix dilatation and fetal head station during labor. The system was designed to provide continuous and accurate assessment of the progression of labor. The computerized labor-monitor (CLM) was tested in the laboratory and was studied in over 95 women during labor. The laboratory test showed that the mean error of measurement is 0.1 mm with standard deviation of 1.14 mm. In the clinical experiments, safety of the various system components was demonstrated and partograms were compared to manual measurements. The systematic error of the fetal head station measurement is estimated as 10-20%, depending on patient's anatomy. In addition, the clinical tests indicated that measurements of the changes of both cervix dilatation and fetal head station are feasible. The CLM is expected to change patient management in the labor room. It will enable timely recognition of abnormal labor patterns such as dysfunctional and precipitous labor. Continuous accurate data will allow earlier diagnosis and intervention that is very likely to improve both mother's and baby's clinical outcome.