Assessment of Coupling between Trans-Abdominally Acquired Fetal ECG and Uterine Activity by Bivariate Phase-Rectified Signal Averaging Analysis

Abstract

Couplings between uterine contractions (UC) and fetal heart rate (fHR) provide important information on fetal condition during labor. At present, couplings between UC and fHR are assessed by visual analysis and interpretation of cardiotocography. The application of computerized approaches is restricted due to the non-stationarity of the signal, missing data and noise, typical for fHR. Herein, we propose a novel approach to assess couplings between UC and fHR, based on a signal-processing algorithm termed bivariate phase-rectified signal averaging (BPRSA).MethodsElectrohysterogram (EHG) and fetal electrocardiogram (fECG) were recorded non-invasively by a trans-abdominal device in 73 women at term with uneventful singleton pregnancy during the first stage of labor. Coupling between UC and fHR was analyzed by BPRSA and by conventional cross power spectral density analysis (CPSD). For both methods, degree of coupling was assessed by the maximum coefficient of coherence (CPRSA and CRAW, respectively) in the UC frequency domain. Coherence values greater than 0.50 were consider significant. CPRSA and CRAW were compared by Wilcoxon test.ResultsAt visual inspection BPRSA analysis identified coupled periodicities in 86.3% (63/73) of the cases. 11/73 (15%) cases were excluded from further analysis because no 30 minutes of fECG recording without signal loss was available for spectral analysis. Significant coupling was found in 90.3% (56/62) of the cases analyzed by BPRSA, and in 24.2% (15/62) of the cases analyzed by CPSD, respectively. The difference between median value of CPRSA and CRAW was highly significant (0.79 [IQR 0.69–0.90] and 0.29 [IQR 0.17–0.47], respectively; p<0.0001).ConclusionBPRSA is a novel computer-based approach that can be reliably applied to trans-abdominally acquired EHG-fECG. It allows the assessment of correlations between UC and fHR patterns in the majority of labors, overcoming the limitations of non-stationarity and artifacts. Compared to standard techniques of cross-correlations, such as CPSD, BPRSA is significantly superior.

Brain sparing effect in growth‐restricted fetuses is associated with decreased cardiac acceleration and deceleration capacities: a case–control study

“…human IUGR fetuses) the AC and DC decrease . Thus, PRSA analysis is capable of capturing the ANS activation in the case of acute hypoxic insult, and to identify lower ANS reactivity in IUGRs confirming the potential value of the PRSA method for fetal monitoring …”

Effect of Music on Labor Pain Relief, Anxiety Level and Postpartum Analgesic Requirement: A Randomized Controlled Clinical Trial

“…Analysis of FHR recordings provides valuable information about the fetal homeostasis. There are different methods to analyze FHR [19,20]. NST is the most popular screening test of fetal well-being used all over the world.…”

Analysis of the fetal cardio-electrohysterographic coupling at the third trimester of gestation in healthy women by Bivariate Phase-Rectified Signal Averaging

“…We replicated the methodology conducted by Casati et al [10], in which both transabdominal electrocardiogram and EHG were recorded at 900 Hz in the third trimester of pregnancy and stored for off-line analysis. The maternal uterine electrical activity was extracted from the slow wave of the EHG, i.e., its envelope, and the fetal heart rate (FHR) time series were extracted using the Monica DK software (version 1.9; Monica Healthcare).…”

“…Changes of FHR depict the influence of the maturation of the fetal autonomic nervous system during pregnancy progression [9]. Signal processing techniques can also provide a reproducible numerical assessment of the relationship between FHR and EHG [10,11]. This physiological phenomenon is known as the fetal cardio-electrohysterographic coupling (FCEC), and it indicates the influence of uterine electrical activity on FHR.…”

“…This physiological phenomenon is known as the fetal cardio-electrohysterographic coupling (FCEC), and it indicates the influence of uterine electrical activity on FHR. At present, FCEC is indirectly evaluated by clinicians using visual analysis of cardiotocographic data during labor [10], which is subjective and demands specialized individual training. Thus, such phenomenon has been poorly explored during the antenatal period.…”