title: Computerized analysis of fetal heart rate variability signal during the stages of labor.
abstract: OBJECTIVE
  To analyze computerized cardiotocographic (cCTG) parameters (baseline fetal heart rate, baseline FHR; short term variability, STV; approximate entropy, ApEn; low frequency, LF; movement frequency, MF; high frequency, HF) in physiological pregnancy in order to correlate them with the stages of labor. This could provide more information for understanding the mechanisms of nervous system control of FHR during labor progression.
  
  
  METHODS
  A total of 534 pregnant women were monitored on cCTG from the 37th week before the onset of spontaneous labor and during the first and the second stage of labor. Statistical analysis was performed using Kruskal-Wallis test and Wilcoxon rank-sum test with the Bonferroni adjusted α (< 0.05).
  
  
  RESULTS
  Statistically significant differences were seen between baseline FHR, MF and HF (P < 0.001), in which the first two were reduced and the third was increased when compared between pre-labor, and the first and second stages of labor. Differences between some of the stages were found for ApEn, LF and for LF/(HF + MF), where the first and the third were reduced and the second was increased.
  
  
  CONCLUSIONS
  cCTG modifications during labor may reflect the physiologic increased activation of the autonomous nervous system. Using computerized fetal heart rate analysis during labor it may be possible to obtain more information from the fetal cardiac signal, in comparison with the traditional tracing.
authors.affiliation: Department of Obstetrical-Gynaecological and Urological Science and Reproductive Medicine of the Federico II University, Naples, Italy.
authors.forename: Maria Laura
authors.initials: ML
authors.lastname: Annunziata
authors.affiliation: Department of Obstetrical-Gynaecological and Urological Science and Reproductive Medicine of the Federico II University, Naples, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Tagliaferri
authors.affiliation: Department of Obstetrical-Gynaecological and Urological Science and Reproductive Medicine of the Federico II University, Naples, Italy.
authors.forename: Francesca Giovanna
authors.initials: FG
authors.lastname: Esposito
authors.affiliation: Department of Obstetrical-Gynaecological and Urological Science and Reproductive Medicine of the Federico II University, Naples, Italy.
authors.forename: Natascia
authors.initials: N
authors.lastname: Giuliano
authors.affiliation: Department of Obstetrical-Gynaecological and Urological Science and Reproductive Medicine of the Federico II University, Naples, Italy.
authors.forename: Flavia
authors.initials: F
authors.lastname: Mereghini
authors.affiliation: Department of Obstetrical-Gynaecological and Urological Science and Reproductive Medicine of the Federico II University, Naples, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Di Lieto
authors.affiliation: Department of Obstetrical-Gynaecological and Urological Science and Reproductive Medicine of the Federico II University, Naples, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Campanile
mesh_terms: D000328:Adult; D015148:Cardiotocography / Q000379:methods*; D005260:Female; D006340:Heart Rate, Fetal / Q000502:physiology*; D006801:Humans; D007743:Labor, Obstetric / Q000502:physiology*; D011247:Pregnancy
keywords: autonomic nervous system; fetal heart rate; fetal monitoring; obstetric labor; spectrum analysis