Noninvasive antepartum recording of fetal S-T segment with a newly developed 151-channel magnetic sensor system

Objective: The objective of this study was to evaluate the efficiency of the detection of the S-T segment in the fetal PQRST complex that is recorded in the antepartum period with the use of a newly developed noninvasive 151-channel magnetic sensor array. Study Design: One hundred two fetal magnetocardiographic recordings were performed on normal fetuses with gestational ages that ranged from 27.5 to 39.5 weeks. After the removal of the interfering maternal heart signals, the fetal heart data were inspected to detect the presence of P, QRS, and T segments. Results: The QRS complex was detectable in 100%, the P wave was detectable in 95.1%, and the T wave was detectable in 87.3% of the recordings. Conclusion: Fetal magnetocardiography was recorded successfully, the QRS complex was observed in all subjects, and the T detection rate increased, with the gestational age reaching a peak of 97%. Further study of the S-T segment through the antepartum period could lead to advances in the detection of fetal jeopardy before labor. (Am J Obstet Gynecol 2003;188:1491-7.)