The Study of Correlation between Sound Provoked Test (SPT) and Nonstress Test (NST)

Abstract

Objective To correlate the sound-provoked fetal movement (SPT) detected
by ultrasound with the nonstress test (NST).

Design Cross-sectionalstudy.

Setting Maternal-Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Faculty of Medicine, Chiang Mai University, Thailand.

Subjects and methods From 1st October 1993 to 1st January 1995, both SPT and NST were performed in the same setting in 1,017 occasions on high-risk pregnancies. The SPT test was defined as reactive (normal) when at least one fetal movement was  monographically observed and nonreactive (abnormal) when no fetal movement was detected after the sound-provoke was applied to the felus.

Results lt was found that SPT was an accurate test in detection of reactive NST with high specificity of 96.67o/", however, the sensitivity of the test was rather low (34.14/o).

Conclusion Objectively detected sound-provoked fetal movement may be used as a simple and rapid method of evaluating antenatal surveillance in hight risk situation where an ultrasound is availatbe.