Novel Phonography-Based Measurement for Fetal Breathing Movement in the Third Trimester

Márton Áron Goda,Tamás Telek,Ferenc Kovács

doi:10.3390/s21010211

Márton Áron Goda, Tamás Telek + Show 1 more

Open Access

https://doi.org/10.3390/s21010211

Copy DOI

Abstract

The detailed assessment of fetal breathing movement (FBM) monitoring can be a pre-indicator of many critical cases in the third trimester of pregnancy. Standard 3D ultrasound monitoring is time-consuming for FBM detection. Therefore, this type of measurement is not common. The main goal of this research is to provide a comprehensive image about FBMs, which can also have potential for application in telemedicine. Fifty pregnancies were examined by phonography, and nearly 9000 FBMs were identified. In the case of male and female fetuses, 4740 and 3100 FBM episodes were detected, respectively. The measurements proved that FBMs are well detectable in the 20–30 Hz frequency band. For these episodes, an average duration of 1.008 ± 0.13 s (p < 0.03) was measured in the third trimester. The recorded material lasted for 16 h altogether. Based on these measurements, an accurate assessment of FBMs could be performed. The epochs can be divided into smaller-episode groups separated by shorter breaks. During the pregnancy, the rate of these breaks continuously decreases, and episode groups become more contiguous. However, there are significant differences between male and female fetuses. The proportion of the episodes which were classified into minimally 10-member episode groups was 19.7% for males and only 12.1% for females, even at the end of the third trimester. In terms of FBM detection, phonography offers a novel opportunity for long-term monitoring. Combined with cardiac diagnostic methods, it can be used for fetal activity assessment in the third trimester and make measurement appreciably easier than before.

Highlights

Fetal breathing movement (FBM) is a peculiar phenomenon of intrauterine life
In the 20–30 Hz frequency band, we found that fetal breathing movement (FBM) epochs are formed by those episode groups which can be separated by short breaks
We have shown that the intensity of episodes significantly changes during the pregnancy, the number of short breaks between FBMs decreases, the episode groups become more and more contiguous, and that there are significant differences between male and female fetuses

Summary

Introduction

Fetal breathing movement (FBM) is a peculiar phenomenon of intrauterine life. It is special because there is no oxygen uptake (which is normally called breathing); only the diaphragm contraction and relaxation are detectable [1]. During the contraction and relaxation of the diaphragm, the surrounding tissues and fluids are moved, which creates sounds that can be recorded on the maternal abdominal wall with a suitable microphone. This means that the FBM can be determined by a novel method using phonography, in addition to the usual ultrasonic measurement. The advantage of this is that the measuring device is definitely much simpler here, and this measurement is not time-dependent (i.e., the sonographer does not have to wait for the FBMs, which are relatively rare) because the passive phonogram recorder can be left on the maternal abdomen for a long time

Objectives

Methods

Results

Discussion

Conclusion