New indexes from the fetal heart rate analysis for the identification of severe intra uterine growth restricted fetuses.

This study proposes new indexes extracted from fetal heart rate signal in order to identify intrauterine growth restricted (IUGR) fetuses and separate them from healthy small for gestational age ones (SGA). Unfortunately evidence-based guidelines for clinical surveillance are poor and lack of reliable indexes. Therefore we proposed new parameters: the Lempel Ziv complexity (LZC) and the multiscale entropy (MSE). The results show that the LZ complexity is able to significantly discriminate the severe IUGR (preterm delivered) from moderate IUGR (at term delivered) and healthy fetuses. Moreover the k-mean cluster analysis applied to these indexes was able to gather the severe IUGRs and to separate them from both not severe IUGRs and normal fetuses, which were included in the same cluster. The cluster analysis provides good values of sensitivity and accuracy.