Fetal cardiac function examination
During pregnancy ultrasound CTG is widely used as a means of assessing fetal cardiac function. Though the method presents no risks during the usual clinical test periods, for home monitoring non-invasive, passive methods seem to be more appropriate.
Recording feta heart sound with microphone
With the help of a microphone embedded in a regular stethoscope one can listen to the heart sounds of the fetus and calculate heart rate from the signals gained therefrom. The sound recorded through the mother’s tummy contains the heart sounds of both the mother and the fetus but in different frequency ranges so they can be separated digitally.
Monitoring fetal heart rate at home
As recording heart rate is a passive method (only a stethoscope is used), monitoring fetal heart rate and listening to the hearts sounds can be performed at will in one’s home with the help of a smartphone or computer.