Estimation of PSD and Non-linear Entropy Parameters of FHRV

Changes observed in fetal heart rate (FHR) in response to stress induced by uterine contractions is recorded using Cardiotocography (CTG). More than three decades of research on electronic fetal monitoring (EFM) revealed that the study of FHR variability helps in assessing fetal well being during labor. Based on characteristics of FHR changes in neonatal outcomes were predicted. Research studies have not demonstrated any significant reduction in overall perinatal mortality with the use of continuous EFM. Hence, the area of FHR monitoring still faces challenges related to disagreements over the clinical interpretation of FHR, the absence of standard terminology, and significant differences in how to define and handle unsettling FHR patterns. Algorithms developed to extract various features from FHR signals help in FHR variability analysis. To determine the power spectrum density of FHR signals at various frequencies, the current work conducted a frequency domain analysis of FHR tracings. The nonlinearity in these signals due to FHR variability was measured by calculating the statistical entropy parameters of non-linearity.