The Relationship of Weekly Monitoring of the Radial Artery Pulse Harmonics During Pregnancy Process

Objectives: The pulse wave fluctuations during pregnancy exhibit distinct characteristics that represent both the pregnancy and the fetus. However, these fluctuations, which contain more frequency domain information, have not yet been studied for diagnostic purposes. Our objective was to quantify these pulse waveforms and gather empirical evidence regarding their relationship with both pregnancy and fetal sex. Methods: We collected wrist pulse data from 36 pregnant women (420 datasets) and 50 nonpregnant women using a pressure sensor. We applied Fourier transformation to analyze these pulse waveforms and extract their harmonics in frequency domain. Subsequently, we conducted a statistical analysis to compare these harmonics between pregnant and nonpregnant women to estimate the differences. To validate our findings, we employed machine-learning techniques to assess the utility of these harmonics. Results: We observed a significant increase in the first and second harmonics in the right hand of the pregnant women, with a distinct pattern observed for these harmonics in the left hand. Furthermore, the differences in the top three harmonics between both hands were more evident, particularly in male fetuses, as we analyzed the monthly changes in harmonic differences, revealing stronger magnitudes in the early months. Additionally, our model accurately predicted fetal sex after 12 weeks over 70% accuracy using decision tree techniques. Conclusions: The pulse waveforms of the pregnant women displayed distinct signals, and the observed differences in harmonics between both hands were notable, especially with regard to fetal sex. This evidence could inform prenatal care practices and help research the maternal-fetal relationship.