Background: Amniotic fluid volume is an indicator of fetal well-being in second and
third trimesters of pregnancy and oligohydramnios is diagnosed when this volume is less
than 500 ml. Flow velocity waveforms of the renal arteries by doppler ultrasonography
provide a sensitive method to predict changes in amniotic fluid dynamics and index in
early stages of pregnancy.
Aim: to determine the relation of renal artery flow velocity waveforms with normal
pregnancies and with pregnancies complicated by oligohydraminos using doppler
ultrasonography.
Methods: a doppler ultrasound device was used to assess the renal artery pulsatility index
(PI), resistance index (RI), systolic/diastolic (S/D) ratio. 3 consecutive waveforms from
each fetus were traced and the average values used for final analysis.
Results: Maternal age ranged from (20 -40) years. Fetal age ranged from (21 -38) weeks.
In oligohydramnios cases, median of (PI) in Lt kidney was (1.99) and in Rt kidney was
(2.14), while median of (RI) in Lt kidney was (0.8372) and in Rt kidney was (0.852).
While in normal cases median of (PI) in Lt kidney was (1.4584) and in Rt kidney was
(1.4124), while median of (RI) in Lt kidney was (0.71) and in Rt kidney was (0.69988)
Conclusion: There is a relation between renal arteries flow velocity waveforms and
oligohydraminos by using doppler Ultrasonography. Oligohydramnios with markedly
changes in PI & RI values especially in the third trimester is an indicator for rapid delivery
to save fetal life. Oligohydramnios could be predicted according to changes in PI & RI
values.