title: Extraction, quantification and characterization of uterine magnetomyographic activity--a proof of concept case study.
abstract: OBJECTIVE
  The objective was to extract, quantify and characterize the uterine magnetomyographic (MMG) signals that correspond to the electrophysiological activity of the uterus.
  
  
  METHODS
  Transabdominal MMG recordings with high spatial-temporal resolution were performed with the use of the 151 non-invasive magnetic sensor system. The extraction, quantification and characterization procedures were developed and applied to representative MMG signals that were recorded from a pregnant woman at regular intervals starting at 37 weeks of gestation until the subject reached active labor.
  
  
  RESULTS
  Multiple MMG recordings were successfully performed on the subject before she went into active labor. The extracted MMG burst activity showed a statistically significant correlation (r=0.2; p<0.001) with the contractile events perceived by mothers. The time-frequency analysis of the burst activity showed a power shift towards higher-frequency at 48 h before the subject went into active labor as compared to earlier recordings. Further there was a gradual increase in the synchrony in the higher-frequency band as the subject reached close to active labor.
  
  
  CONCLUSIONS
  The non-invasive recording of the magnetic signals of pregnant uterus with high spatial-temporal resolution can provide an insight into the preparatory phase of labor and has the potential of predicting term and preterm labor.
authors.affiliation: Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, 4301 W. Markham Slot 518, Little Rock, AR 72205, USA. eswaranhari@uams.edu
authors.forename: Hari
authors.initials: H
authors.lastname: Eswaran
authors.forename: Rathinaswamy B
authors.initials: RB
authors.lastname: Govindan
authors.forename: Adrian
authors.initials: A
authors.lastname: Furdea
authors.forename: Pam
authors.initials: P
authors.lastname: Murphy
authors.forename: Curtis L
authors.initials: CL
authors.lastname: Lowery
authors.forename: Hubert T
authors.initials: HT
authors.lastname: Preissl
mesh_terms: D004576:Electromyography / Q000379:methods*; D004594:Electrophysiology; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000502:physiology*; D008280:Magnetics; D007752:Obstetric Labor, Premature / Q000175:diagnosis; D011247:Pregnancy / Q000502:physiology; D014590:Uterine Contraction / Q000502:physiology*; D014599:Uterus / Q000502:physiology