Preliminary Study on Wearable Patch Device with EHG Envelope Peak as Feature Parameter for Preterm Birth Monitoring

Uterine contraction is a critical activity of pregnancy monitoring and can be used to predict preterm birth. Recently, wearable uterine EMG measuring devices have been introduced to monitor pregnancy such as pre-term birth. In this work, we designed a prototype of abdomen attachable patch device as uterine EMG signal acquisition circuits. Also, the number of peak points of the EHG signal envelope was studied as new feature parameter for discrimination of preterm birth. Multi-channel uterine EMG signals could be measured simultaneously and the device size is about 60 * 50 mm2. Multi-channel abdominal ECG+EMG signals of test subject could be measured successfully with this patch devices and the measured signals could be communicated wirelessly to other smart devices successfully. To extract EMG signal from ECG+EMG complex, we designed differential mode circuit configuration and test results shows good extraction performance. The number of envelope peak points of EHG signals as a new feature parameter is expected to be useful in predicting preterm delivery risk.