Maternal perception of sound-provoked fetal movement as a test of antepartum fetal wellbeing

Maternal perception of sound-provoked fetal movement test was studied on 506 occasions in 443 women with obstetric or medical antenatal risk factors after 26 weeks gestation. The response was compared with a nonstress test (NST) performed immediately after a three-second vibroacoustic stimulation with an electronic artificial larynx. A positive response to sound stimulation, recorded as a fetal movement by the mother, occurred on 497 occasions (97.3%) and was accompanied by a reactive NST on 484 occasions; giving a specificity of 99.6 per cent and a negative predictive value of 97.4 per cent. An inconclusive or negative response to sound (2.7%) had a sensitivity of 35.0 per cent and a positive predictive value for a nonreactive NST of 77.8 per cent. Results of sound-provoked fetal movement test and NST, performed within a week of delivery, in 434 women were compared with fetal outcome. The maternal perception of sound-provoked fetal movement test had better specificity (99.1% vs 96.9%), positive predictive value (55.6% vs 35.0%) for poor fetal outcome than the NST, although its sensitivity (50.0% vs 70.0%) and negative predictive value (98.8% vs 99.3%) were lower. Maternal perception of sound-provoked fetal movement test may suffice as an inexpensive and simple method of evaluating antepartum fetal well-being in risk situations. When the mother does not feel any sound provoked fetal movement, NST is then performed. This clinical application can be helpful in a primary health care setting where rapid assessment of fetal health at risk is required.