title: Repeatability of measurement of uterine artery pulsatility index using transvaginal color Doppler.
abstract: OBJECTIVE
  To assess the repeatability of measuring the pulsatility index of the uterine arteries using transvaginal color Doppler at 23 weeks of gestation.
  
  
  METHODS
  The pulsatility index was measured in 100 women with singleton pregnancies attending for routine transvaginal Doppler examination of the uterine arteries at 23 weeks. To assess the repeatability of different components of variability, six measurements of the uterine artery pulsatility index were made on one of the uterine arteries in each patient.
  
  
  RESULTS
  Six measurements of the pulsatility index were successfully measured in all 100 patients, resulting in a total of 600 measurements. The repeatability was unrelated to the pulsatility index. On 95% of occasions the intraobserver, interobserver and waveform tracing repeatability was less than 0.24, 0.27 and 0.14, respectively.
  
  
  CONCLUSIONS
  Measurement of the pulsatility index using transvaginal color Doppler is highly reproducible when the examination is carried out by well-trained operators.
authors.affiliation: Harris Birthright Research Centre, King's College Hospital, London, UK.
authors.forename: A T
authors.initials: AT
authors.lastname: Papageorghiou
authors.forename: M S
authors.initials: MS
authors.lastname: To
authors.forename: C K
authors.initials: CK
authors.lastname: Yu
authors.forename: K H
authors.initials: KH
authors.lastname: Nicolaides
mesh_terms: D001158:Arteries; D005260:Female; D006801:Humans; D015588:Observer Variation; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011673:Pulsatile Flow; D015203:Reproducibility of Results; D018615:Ultrasonography, Doppler, Color; D016216:Ultrasonography, Prenatal; D014599:Uterus / Q000098:blood supply*