title: [The evaluation of umbilical arterial Doppler spectrum fractal characterization in obstetrics].
abstract: OBJECTIVE
  To evaluate the clinical value of fetal umbilical arterial Doppler spectrum fractal.
  
  
  METHODS
  104 cases with 22-41 gestational weeks were included, and divided into two groups: normal pregnant group, 59 cases; abnormal pregnant group, 45 cases. Umbilical arterial Doppler spectrum were obtained by color Doppler ultrasound, then Doppler signal were transformed into computer through sound-frequency, and fractal were calculated.
  
  
  RESULTS
  The fractal was 1.83 +/- 0.03 in normal pregnant group. The frequency of abnormal fractal was significantly higher in abnormal pregnant group than that in normal pregnant group (P < 0.001). Compared with the ratio of peak systolic to lowest diastolic flow velocity (S/D), the fractal was more sensitive than S/D ratio in abnormal pregnancy (P < 0.05). There were significant correlation between fractal and gestational weeks (r = 0.266).
  
  
  CONCLUSIONS
  Fractal responses to complexity of umbilical arterial blood flow, and it is a better parameter than S/D ratio in monitoring abnormal umbilical arterial blood flow.
authors.affiliation: Obstetrics and Gynecology Hospital of Shanghai Medical University.
authors.forename: C
authors.initials: C
authors.lastname: Chang
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging; D005311:Fetal Hypoxia / Q000000981:diagnostic imaging; D017709:Fractals; D006801:Humans; D011225:Pre-Eclampsia / Q000000981:diagnostic imaging; D011247:Pregnancy; D018615:Ultrasonography, Doppler, Color; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries / Q000000981:diagnostic imaging*