Reliable nonlinear indices for fetal heart rate variability signal analysis

The paper aims to present and discuss results obtained in the analysis of Fetal Heart Rate (FHR) time series, obtained from Normal and IUGR populations of fetuses. Methods adopted considered both traditional time domain approaches as well as new indices in the nonlinear field such as entropy measures, complexity parameters and indices derived from phase rectified signal averaging method. Results shows that i) nonlinear parameters provide reliable indications about pathophysiologic fetal states; ii) could support clinical fetal monitoring by new measures; iii) should be considered to design novel fetal monitoring systems.