title: Fetal renal pulsed Doppler waveform in prolonged pregnancies.
abstract: OBJECTIVE
  Our purpose was to determine Doppler waveforms of the fetal human renal artery in prolonged pregnancy in the presence or absence of oligohydramnios.
  
  
  METHODS
  Fifty patients at or after 40 weeks were studied. Ultrasonography was performed to determine the amniotic fluid index by the four-quadrants technique. Two groups of patients were obtained on the basis of the amniotic fluid index. Group 1 had an amniotic fluid index > 5 (normal) (n = 33); group 2 had amniotic fluid index < or = 5 (oligohydramnios) (n = 17). Umbilical artery and fetal renal pulsed Doppler waveforms were determined and analyzed. The fetal renal artery systolic-to-diastolic ratio of the two groups was compared.
  
  
  RESULTS
  Fetuses with a low amniotic fluid index had a significantly higher ratio. A significant negative correlation coefficient between amniotic fluid index and fetal renal systolic/diastolic ratio was found (r = -0.435 and p < 0.01).
  
  
  CONCLUSIONS
  In prolonged pregnancies there is a significant relationship between the amniotic fluid index and the fetal renal systolic/diastolic ratio. In pregnancies associated with oligohydramnios the systolic/diastolic ratio is significantly higher than in those with normal amniotic fluid volume. These data suggest that intrarenal flow in prolonged pregnancies complicated with oligohydramnios is significantly different.
authors.affiliation: Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, NC 27157.
authors.forename: J C
authors.initials: JC
authors.lastname: Veille
authors.forename: M
authors.initials: M
authors.lastname: Penry
authors.forename: E
authors.initials: E
authors.lastname: Mueller-Heubach
mesh_terms: D000328:Adult; D000653:Amniotic Fluid; D001034:Apgar Score; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001835:Body Weight; D005260:Female; D005333:Fetus / Q000196:embryology* / Q000502:physiology; D006801:Humans; D007668:Kidney / Q000098:blood supply* / Q000000981:diagnostic imaging; D008423:Maternal Age; D016104:Oligohydramnios / Q000000981:diagnostic imaging; D011247:Pregnancy; D011273:Pregnancy, Prolonged / Q000502:physiology*; D012077:Renal Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D016216:Ultrasonography, Prenatal