Uterine electromyography for discrimination of labor imminence in women with threatened preterm labor under tocolytic treatment

Abstract

As one of the main aims of obstetrics is to be able to detect imminent delivery in patients with threatened preterm labor, the techniques currently used in clinical practice have serious limitations in this respect. The electrohysterogram (EHG) has now emerged as an alternative technique, providing relevant information about labor onset when recorded in controlled checkups without administration of tocolytic drugs. The studies published to date mainly focus on EHG-burst analysis and, to a lesser extent, on whole EHG window analysis. The study described here assessed the ability of EHG signals to discriminate imminent labor (< 7 days) in women with threatened preterm labor undergoing tocolytic therapy, using both EHG-burst and whole EHG window analyses, by calculating temporal, spectral, and non-linear parameters. Only two non-linear EHG-burst parameters and four whole EHG window analysis parameters were able to distinguish the women who delivered < 7 days from the others, showing that EHG can provide relevant information on the approach of labor, even in women with threatened preterm labor under the effects of tocolytic therapy. The whole EHG window outperformed the EHG-burst analysis and is seen as a step forward in the development of real-time EHG systems able to predict imminent labor in clinical praxis. Graphical abstract The ability of EHG recordings to predict imminent labor (< 7 days) was analyzed in preterm threatened patients undergoing tocolytic therapies by means of EHG-burst and whole EHG window analysis. The non-linear features were found to have better performance than the temporal and spectral parameters in separating women who delivered in less than 7 days from those who did not.

Design and Assessment of a Robust and Generalizable ANN-Based Classifier for the Prediction of Premature Birth by means of Multichannel Electrohysterographic Records

“…Peak to peak amplitude was computed because it is directly related to the intensity of uterine electrical activity. A set of spectral parameters including mean frequency [48], dominant frequency [20,37], H/L ratio, which represents the relation between the energy computed in (0.34-1 Hz) with respect to the energy computed in (0.2-0.34 Hz), and the deciles of the power spectrum density were selected since they are related to cell excitability [19,49]. We also included a set of nonlinear parameters that have been widely used to characterize the electrophysiological state of the uterus and other bioelectrical signals such as EEG, including sample entropy [26], spectral entropy [50], fuzzy entropy [51], Lempel-Ziv complexity (binary and multistate versions) [25], time reversibility [23], Poincaré plot metrics (SD1, SD2, SDRR, and SD1/SD2) [52], and Higuchi's fractal dimension [53].…”

“…[46,47], bipolar signals were digitally filtered in that range (5 th -order Butterworth band-pass in forward and backward direction to obtain zero-phase shift). Instead of traditional EHG-burst analysis, we preferred to perform the whole EHG window analysis, which has been shown to provide relevant information for predicting preterm labor and is more easily integrated in real-time applications [38,48]. In this respect, signal sections with evident motion artifacts were discarded from the single channels by visual inspection.…”

“…Figure 1 shows the sample size of preterm and term labor records for each singlechannel and multichannel analysis. EHG signals were divided into 120 s analysis windows with a 50% overlap in order to include representative sections of the recording at a reasonable computational cost [48].…”

Robust Characterization of the Uterine Myoelectrical Activity in Different Obstetric Scenarios

“…Several studies have focused on using EHG parameters to identify effective labor contractions in term and preterm pregnancies [ 10 , 12 , 19 ], even in women with threatened preterm labor undergoing tocolytic therapies [ 20 , 21 ]. Temporal parameters which measure the intensity of contractions such as peak-to-peak amplitude or RMS, and spectral parameters to determine the shift of spectral content to high frequencies when labor approaches, such as mean, median, or dominant frequency, have been used to characterize EHG signals [ 22 ].…”

Early detection of postpartum depression (PPD) for women suffering high-risk pregnancy: An explorative study on self-perceived burden and other prenatal risk factors of immediate PPD among women hospitalized with threatened preterm labour1

“…TPL is not only a physical problem-it also affects a pregnant woman's psychological and emotional status [6]. However, as the research in this area focuses on the causes and biologic effects of TPL [7], few investigators have assessed the mental health of women with TPL before and after delivery. China announced a universal two-child policy in October 2015, which was predicted to increase advanced maternal age-associated TPL in China and bring new challenges to obstetric care [8].In this study, we investigate the prevalence and correlation of two psychological and emotional constructs-self-perceived burden (SPB) and postpartum depression (PPD)-among women hospitalized with TPL at a tertiary care hospital in China PPD-which is characterized by the presence of non-psychotic depressive episodes-is a complex mix of physical, emotional, and behavioural changes that happen to puerpera in the weeks and months after delivery [9][10].…”