title: Nonlinear analysis of biomagnetic signals recorded from the umbilical artery in normal and pre-eclamptic pregnancies.
abstract: OBJECTIVE
  In this study we investigated the hemodynamics of the feto-placental circulation in normal and pre-eclamptic near term pregnancies using the biomagnetometer SQUID. Thirteen abnormal and 25 normal pregnancies were included in this study.
  
  
  METHODS
  The biomagnetic signals were analyzed using nonlinear analysis in order to differentiate these two types of pregnancies.
  
  
  RESULTS
  The application of nonlinear analysis reveal a clear saturation dimension value for pre-eclamptic and non-saturation for normal pregnancies. These findings were statistically significant and were correlated with fetal heart rate monitoring, pH and Apgar score: high biomagnetic cases (140-300 fT/square root Hz) were related with normal patterns, pH>7.25 and Apgar >7, while low biomagnetic recordings (50-110 fT/square root Hz) were connected with abnormal patterns, pH<7.25 and Apgar <7.
  
  
  CONCLUSIONS
  It is suggested that the biomagnetic measurements with SQUID and the application of nonlinear analysis, is a promising procedure in assessing fetal health, especially in high risk pregnancies.
authors.affiliation: Laboratory of Medical Physics, Medical School, Democrition University of Thrace, Alexandroupolis, Greece. aninnos@demokritos.cc.duth.gr
authors.forename: P A
authors.initials: PA
authors.lastname: Anninos
authors.forename: P
authors.initials: P
authors.lastname: Anastasiadis
authors.forename: A
authors.initials: A
authors.lastname: Kotini
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001034:Apgar Score; D002585:Cesarean Section; D005260:Female; D005316:Fetal Distress / Q000175:diagnosis; D005865:Gestational Age; D006340:Heart Rate, Fetal; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007743:Labor, Obstetric; D008280:Magnetics; D008433:Mathematics; D011225:Pre-Eclampsia / Q000503:physiopathology*; D011247:Pregnancy; D014469:Umbilical Arteries / Q000503:physiopathology*