title: Prospective evaluation of renal artery resistance and pulsatility indices in normal pregnant women.
abstract: OBJECTIVE
  To establish normal values for renal artery resistance index (RI) and pulsatility index (PI) during gestation and, by comparison with non-pregnant controls, to determine if pregnancy affects these indices.
  
  
  METHODS
  This was a prospective longitudinal study involving 36 normal pregnant women who underwent a total of 280 examinations at 4-week intervals from the 6th gestational week to the end of pregnancy. High-resolution ultrasound equipment with 'triplex' Doppler facilities was used. RI and PI were obtained for the main arteries of both kidneys. The same evaluation was performed in 15 non-pregnant women as controls.
  
  
  RESULTS
  The mean RI in pregnant and non-pregnant women was the same (0.65 +/- 0.03 for controls and 0.65 +/- 0.02 for the pregnant women). For PI, the values were 1.25 +/- 0.12 for non-pregnant women and 1.18 +/- 0.09 for pregnant women. The only statistical difference (P < 0.05) was found between the PI of the left renal artery in the control group (1.29 +/- 0.20) and that in the pregnant group at the 8-12-week interval of gestational age (1.08 +/- 0.14).
  
  
  CONCLUSIONS
  No significant alterations in renal artery RI and PI occur during normal pregnancy, except for in a subgroup of patients between 8 and 12 weeks of gestation.
authors: Departamento de Ginecologia e Obstetrícia da Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo-USP, Brazil. fdib@keynet.com.br
authors: F R
authors: FR
authors: Dib
authors: G
authors: G
authors: Duarte
authors: M M
authors: MM
authors: Sala
authors: R A
authors: RA
authors: Ferriani
authors: A T
authors: AT
authors: Berezowski
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001783:Blood Flow Velocity / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008137:Longitudinal Studies; D011247:Pregnancy / Q000502:physiology*; D011446:Prospective Studies; D012077:Renal Artery / Q000502:physiology*; D014655:Vascular Resistance / Q000502:physiology*