Reyes-Lagos José Javier, Pliego-Carrillo Adriana Cristina, Ledesma-Ramírez Claudia Ivette, Peña-Castillo Miguel Ángel, García-González María Teresa, Pacheco-López Gustavo, Echeverría Juan Carlos
Faculty of Medicine, Autonomous University of the State of Mexico (UAEMex), Toluca 50180, Mexico.
Basic Sciences and Engineering Division (CBI), Campus Iztapalapa, Metropolitan Autonomous University (UAM), Mexico City 09340, Mexico.
Entropy (Basel). 2020 Jul 22;22(8):798. doi: 10.3390/e22080798.
Phase Entropy () was recently introduced for evaluating the nonlinear features of physiological time series. has been demonstrated to be a robust approach in comparison to other entropy-based methods to achieve this goal. In this context, the present study aimed to analyze the nonlinear features of raw electrohysterogram (EHG) time series collected from women at the third trimester of pregnancy (TT) and later during term active parturition (P) by . We collected 10-min longitudinal transabdominal recordings of 24 low-risk pregnant women at TT (from 35 to 38 weeks of pregnancy) and P (>39 weeks of pregnancy). We computed the second-order difference plots (SODPs) for the TT and P stages, and we evaluated the by modifying the value, a coarse-graining parameter. Our results pointed out that in TT is characterized by a higher likelihood of manifesting nonlinear dynamics compared to the P condition. However, both conditions maintain percentages of nonlinear series higher than 66%. We conclude that the nonlinear features appear to be retained for both stages of pregnancy despite the uterine and cervical reorganization process that occurs in the transition from the third trimester to parturition.
相位熵（）最近被引入用于评估生理时间序列的非线性特征。与其他基于熵的方法相比，已被证明是实现这一目标的一种稳健方法。在此背景下，本研究旨在通过分析从妊娠晚期（TT）及之后足月分娩活跃期（P）的女性收集的原始子宫电图（EHG）时间序列的非线性特征。我们收集了24名低风险孕妇在TT期（妊娠35至38周）和P期（妊娠>39周）的10分钟纵向经腹记录。我们计算了TT期和P期的二阶差分图（SODP），并通过修改粗粒化参数的值来评估。我们的结果指出，与P期相比，TT期表现出非线性动力学的可能性更高。然而，两种情况的非线性序列百分比均保持在66%以上。我们得出结论，尽管从妊娠晚期到分娩的过渡过程中发生了子宫和宫颈的重组过程，但妊娠两个阶段的非线性特征似乎都得以保留。
