Effect of Fetal Movements and Fetal Breathing on Fetal Middle Cerebral Artery Pulsatility Index Measurement

摘要

Objective: This study aimed to determine the effect of fetal movements on the MCA pulsatility index (PI) and quantify the fall of MCA PI after initiation of fetal movements and/or breathing, and the time taken to recover from a fall below the 5th percentile. Methods: 16 women with appropriate for gestational age (AGA) fetuses and 16 women with small for gestational age (SGA) fetuses were recruited. MCA PI during “no movement” state was compared with MCA PI values during fetal body movements and breathing movements. Results: MCA PI measurements with body or breathing movements were significantly (p 0.005) lower as compared to that observed without movements. MCA PI started rising immediately after cessation of body movements and/or breathing movements. Conclusions: MCA PI with fetal body or breathing movements is significantly lower as compared to that observed in the quiet state. If MCA PI measurement is below 5th centile, it should be measured again up to 90 seconds after cessation of fetal body and/or breathing movements in order to minimize false positive diagnosis of cerebral sparing effect in SGA as well as AGA fetuses.