We used Gaussian modeling to depict the changes in finger photoplethysmographic (PPG) pulse during pregnancy in healthy women. We enrolled 70 healthy pregnant women and recorded their PPG pulses in 11–13 gestational weeks, 20–22 gestational weeks, and 37–39 gestational weeks. Three independent positive Gaussian functions were utilized to decompose the pulses, and each Gaussian function extracted three key parameters: the peak amplitude (H), the peak position (T), and the half-width (W). The method of ANOVA and post-hoc multiple comparisons of mathematical statistics were utilized to study the differences of these parameters between the three trimesters. We found that in the first trimester H1 increased significantly (H1: 49.7±10.3 versus 52.9±6.9, p<0.05). T2 and T3 increased in the first trimester (T2: 28.1±2.8 versus 28.4±2.2, p>0.05; T3: 54.3±4.2 versus 56.3±4.3, p<0.01), then decreased significantly (T2: 28.4±2.2 versus 27.3±2.2, T3: 56.3±4.3 versus 54.7±5.2, p<0.05). H1 is associated with cardiac output, and T2 and T3 are associated with peripheral vascular resistance. The results of this study were consistent with the conclusion that healthy pregnant women exhibited high flow state of the cardiovascular system and their peripheral vascular resistance decreased first and then gradually recovered during pregnancy. This study indicated that PPG pulse could also reflect the changes in the maternal cardiovascular system during pregnancy.

中文翻译：

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健康怀孕期间 PPG 脉冲高斯模型参数的变化

我们使用高斯模型来描述健康女性怀孕期间手指光电体积描记 (PPG) 脉冲的变化。我们招募了 70 名健康孕妇，并在 11-13 孕周、20-22 孕周和 37-39 孕周记录了她们的 PPG 脉搏。利用三个独立的正高斯函数对脉冲进行分解，每个高斯函数提取三个关键参数：峰值幅度（H), 峰值位置 (吨) 和半角 (W）。采用方差分析和数理统计事后多重比较的方法来研究这些参数在三个三个月之间的差异。我们发现在头三个月H1显着增加（H1：49.7±10.3相对52.9±6.9,p<0.05）。吨2和吨3头三个月增加（吨2：28.1±2.8相对28.4±2.2,p>0.05;吨3：54.3±4.2相对56.3±4.3,p<0.01)，然后显着下降 (吨2：28.4±2.2相对27.3±2.2,吨3：56.3±4.3相对54.7±5.2,p<0.05）。H1与心输出量有关，并且吨2和吨3与外周血管阻力有关。本研究结果与健康孕妇在孕期心血管系统呈现高流量状态，外周血管阻力先下降后逐渐恢复的结论相吻合。本研究表明，PPG脉搏也可以反映孕期母体心血管系统的变化。