Graphic & Audio Display of  Maternal & Fetal HRV

Real time sonification of maternal and fetal heart rate

Up until now, although the fetal and maternal heart rate were  recorded simultaneously in realtime, the data was first converted into music at a later date. This was because the previously developed technology did not allow a realtime conversion into music. Due to this, some of the temporal relationships of maternal and fetal heart beats were lost.


We have now developed  a unique device that will allow for the non-invasive collection of fetal and maternal heart rate and it's immediate sonification (conversion into music). Thus, the exact temporal relationship of maternal and fetal heart beats remains undisturbed, as recorded.

This page contains some of the first results, recorded in September 2011.


In the examples of heart rate sonification on this site, the instantaneous heart rate has been calculated at every new heart beat and given a musical note value, according to whether the rate is rising or falling. Accordingly, higher heart rates will produce higher notes; lower rates will produce lower notes. These notes are also instantaneously triggered by each new heart beat, thus preserving the temporal aspects of heart rate variability.  Longer or shorter inter-beat intervals will produce longer or shorter notes respectively. Also, the pitch will only change when the heart rate changes, so that a heart rate that remains constant over two or more beats will produce a note that will be held so long until the heart rate changes.

From fetal & maternal heart rate variability :

hr score

to music:


1 Jolin & Joelle Marie Grace

2  Anja & child

3  Sylvia & child

4  Heart rate rhythms


Information on the sonification 
of fetal and maternal heart rate