title: Aerobic exercise during pregnancy and presence of fetal-maternal heart rate synchronization.
abstract: It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization.
  
  
  METHODS
  In 40 pregnant women at the 36th week of gestation, 21 of whom exercised regularly, we acquired 18 min. RR interval time series obtained simultaneously in the mothers and their fetuses from magnetocardiographic recordings. The time series of the two groups were examined with respect to their heart rate variability, the maternal respiratory rate and the presence of synchronization epochs as determined on the basis of synchrograms. Surrogate data were used to assess whether the occurrence of synchronization was due to chance.
  
  
  RESULTS
  In the original data, we found synchronization occurred less often in pregnancies in which the mothers had exercised regularly. These subjects also displayed higher combined fetal-maternal heart rate variability and lower maternal respiratory rates. Analysis of the surrogate data showed shorter epochs of synchronization and a lack of the phase coordination found between maternal and fetal beat timing in the original data.
  
  
  CONCLUSIONS
  The results suggest that fetal-maternal heart rate coupling is present but generally weak. Maternal exercise has a damping effect on its occurrence, most likely due to an increase in beat-to-beat differences, higher vagal tone and slower breathing rates.
authors.affiliation: Grönemeyer Institute of Microtherapy, University of Witten/Herdecke, Bochum, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Van Leeuwen
authors.affiliation: Hoglund Brain Imaging Center and Department of Neurology, University of Kansas, Kansas City, Kansas, United States of America.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Gustafson
authors.affiliation: Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke, Herdecke, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Cysarz
authors.affiliation: Research and Development, VISUS Technology Transfer GmbH, Bochum, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Geue
authors.affiliation: Department of Foundational Sciences and Research, East Carolina University, Greenville, North Carolina, United States of America.
authors.forename: Linda E
authors.initials: LE
authors.lastname: May
authors.affiliation: Grönemeyer Institute of Microtherapy, University of Witten/Herdecke, Bochum, Germany.
authors.forename: Dietrich
authors.initials: D
authors.lastname: Grönemeyer
mesh_terms: D000328:Adult; D015444:Exercise; D005260:Female; D005318:Fetal Heart / Q000502:physiology*; D005333:Fetus; D006339:Heart Rate / Q000502:physiology*; D006340:Heart Rate, Fetal / Q000502:physiology*; D006801:Humans; D053798:Magnetocardiography; D033261:Maternal-Fetal Relations / Q000502:physiology*; D009035:Mothers; D011247:Pregnancy; D056152:Respiratory Rate / Q000502:physiology*; D012189:Retrospective Studies