A non-invasive and invasive fetal electrocardiogram real-time monitoring system

The fetal monitoring system discussed here is battery powered and portable. The system includes and ultra-low noise preamplifier for the non-invasively or invasively obtained signals along with an amplifier for a thoracic electrocardiogram (EGG) that is used to cancel the abdominal maternal electrocardiogram (AMECG) of either of the above signals. The AMECG is suppressed in real-time. The AMECG is canceled by using the thoracic ECG as a trigger for developing an average of the AMECG. This average is then subtracted from the abdominal ECG. The resulting abdominal ECG's fetal electrocardiogram (FECG) and electromyographic signals are undisturbed by the cancellation. The FECG signal-to-noise ratio is then improved by using FECG averaging and filtering.<>