title: Transabdominal power Doppler sonography of the normal early placenta.
abstract: OBJECTIVE
  To evaluate how well transabdominal power Doppler sonography, a new method of colour Doppler sonography, visualizes the vasculature of the early placenta.
  
  
  METHODS
  Evaluation of intrachorionic/intraplacental vasculature in 15 normal, singleton gestations of 8 to 18 weeks.
  
  
  RESULTS
  Intrachorionic/intraplacental vessels were identified in all gestations, except the earliest (8 weeks). The number of vessels detected increased with increasing gestational age. Intrachorionic/intraplacental Doppler waveforms of maternal arterial origin were identified in gestations of 8.5, 9.5, and 11.5 weeks.
  
  
  CONCLUSIONS
  Transabdominal power Doppler sonography detects intrachorionic/intraplacental vasculature at least as early as 8.5 weeks. Intervillous arterial flow of maternal origin is present in the first trimester, confirming the results of a recent transvaginal colour Doppler sonographic study, and contradicting earlier studies suggesting that such flow is not present in the first trimester.
authors.affiliation: Department of Radiology, University of Michigan Medical School, Ann Arbor 48109-0326, USA. ronbude@umich.edu
authors.forename: R O
authors.initials: RO
authors.lastname: Bude
authors.forename: C J
authors.initials: CJ
authors.lastname: van deVen
authors.forename: J M
authors.initials: JM
authors.lastname: Rubin
mesh_terms: D005260:Female; D006801:Humans; D010920:Placenta / Q000098:blood supply / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011446:Prospective Studies; D012039:Regional Blood Flow; D018615:Ultrasonography, Doppler, Color