Ishiyama Sayuri, Tahara Takashi, Iwanaga Hiroaki, Ohashi Kazutomo
Maternal and Child Nursing, The Japanese Red Cross Kyushu International College of Nursing, Munakata 811-4157, Japan.
Institute for Basic Medical and Welfare Research, Fukuoka 810-0051, Japan.
Entropy (Basel). 2025 Sep 17;27(9):969. doi: 10.3390/e27090969.
Kolmogorov-Sinai (KS) entropy is an indicator of the chaotic behavior of entire systems from an information-theoretic viewpoint. Here, we used KS entropy values derived from the heart sounds of four fetus-mother pairs to identify the changes in fetal and maternal informational patterns during the four phases of pregnancy (early, mid, late, and postnatal). Time-series data of the heart sounds were reconstructed in a five-dimensional phase space to obtain the Lyapunov spectrum, and KS entropy was calculated. Statistical analyses were then conducted separately for the fetus and mother for the four phases of pregnancy. The fetal KS entropy significantly increased from early pregnancy to the postnatal period (0.054 ± 0.007 vs. 0.097 ± 0.007; < 0.001), whereas the maternal KS entropy decreased in late pregnancy and then significantly increased after birth (0.098 ± 0.002 vs. 0.133 ± 0.003; < 0.001). The increase in KS entropy with the course of fetal gestation reflects an increase in information generation and adaptive capacity during the developmental process. Thus, changes in maternal KS entropy play a dual role, temporarily enhancing physiological stability to support fetal development and helping to rebuild the mother's own adaptive capacity in the postpartum period.
从信息论的角度来看，柯尔莫哥洛夫-西奈（KS）熵是整个系统混沌行为的一个指标。在此，我们使用从四对胎儿-母亲的心音中得出的KS熵值，来识别孕期四个阶段（早期、中期、晚期和产后）胎儿和母亲信息模式的变化。将心音的时间序列数据在五维相空间中进行重构以获得李雅普诺夫谱，并计算KS熵。然后分别针对孕期的四个阶段对胎儿和母亲进行统计分析。胎儿的KS熵从怀孕早期到产后显著增加（0.054±0.007对0.097±0.007；<0.001），而母亲的KS熵在怀孕晚期下降，然后在产后显著增加（0.098±0.002对0.133±0.003；<0.001）。随着胎儿孕期的进展，KS熵的增加反映了发育过程中信息生成和适应能力的增加。因此，母亲KS熵的变化起到了双重作用，暂时增强生理稳定性以支持胎儿发育，并有助于在产后重建母亲自身的适应能力。
