Computerized Quantitative Analysis of Fetal Heart Rate after Acoustic Stimulation in Preterm Pregnancies

Park, Moon Il; Chung, Sung Ro; Koh, Seung Kwon; Hah, Sung Ho; Choi, Gyu Hong

Abstract

Acoustic stimulation test(AST), is currently being used as an alternative tool of nonstress test (NST). However, there are no standard guideline for analysis of AST. Computerized numerical analysis of AST would be helpful for development of diagnostic criteria of AST. Fifty-one normal pre-term pregnancies entered to this study after conventional 20-minutes NST and 10-minutes AST. Acoustic stimulations were performed using Fetal Acoustic Stimulator (Model 146, Corometrics, US). We analyzed the FHR response after acoustic stimulation using our on-line computerized FHR analysis system, HYFM-I & II software. The changes of loss of signal, baseline FHR, variability, number of fetal movements, and number of FHR accelerations were analyzed numerically. The loss of signal was increased about 2 fold(122.61%). The baseline FHR was increased from 144.57bpm to 156.81bpm(8.5%) after acoustic stimulation. Number of fetal movements was increased about 2 fold(from 2.1 to 4.12/10 minutes). FHR variability was also increased from 17.81 bpm to 26.37 bpm. After AST, number of FHR accelaration was increased 55.47%(10sec 10bpm) and 68.42%(15sec 15bpm), respectively. In this study, we acrumulated elemental FHR data using computerized system after AST. These data would be helpful in the accurate analysis of AST and also enable us to develop the objective interpretation system for AST.