Effect of low-sodium diet on uteroplacental circulation.
OBJECTIVE
To study the influence of chronic dietary sodium restriction on uteroplacental circulation.


METHODS
In a randomized trial, Doppler flow velocity waveforms of the uterine and umbilical artery were studied at monthly intervals during pregnancy in 59 women on a low-sodium diet and in 68 controls.


RESULTS
Pulsatility index (PI), resistance index (RI), and A/B ratio of the uterine artery were significantly lower during sodium restriction, whereas PI, RI, and A/B ratio of the umbilical artery were significantly higher.


CONCLUSIONS
The lower resistance indices of the uterine artery during sodium restriction might reflect an increase in pulse pressure/impedance ratio as a result of activation of the renin-angiotensin system. The increase in umbilical artery resistance indices supports the hypothesis that fetal circulation might be altered by chronic dietary sodium restriction.
Delemarre
F M
FM
Department of Obstetrics and Gynecology, University Hospital, St. Radboud Nijmegen, The Netherlands.
van Leest
L A
LA
Jongsma
H W
HW
Steegers
E A
EA
D000328:Adult; D001783:Blood Flow Velocity; D004039:Diet, Sodium-Restricted; D005260:Female; D006801:Humans; D017078:Laser-Doppler Flowmetry; D009426:Netherlands; D010920:Placenta / Q000098:blood supply; D011225:Pre-Eclampsia / Q000517:prevention & control*; D011247:Pregnancy; D011673:Pulsatile Flow; D012964:Sodium / Q000652:urine; D012982:Sodium, Dietary / Q000008:administration & dosage*; D014463:Ultrasonography; D014469:Umbilical Arteries / Q000000981:diagnostic imaging / Q000502:physiology*; D014599:Uterus / Q000098:blood supply*; D014655:Vascular Resistance / Q000502:physiology
D012982:Sodium, Dietary; D012964:Sodium