Citation Information :
Mundkur A, Paladugu S, Yedlapalli S, Vasudeva A, Shivananda RP, Hegde N. Performance of Fetal Renal Artery Doppler Compared with Umbilical Artery Doppler in Mild and Moderate Fetal Growth Restriction: An Observational Study in a Tertiary Care Hospital. Int J Infertil Fetal Med 2020; 11 (1):1-4.
Background: Fetal growth restriction (FGR) and oligoamnios are one of the major reasons of preterm delivery and low birth weight contributing to almost two-third of neonatal mortality. Fetal kidney, in addition to placenta, acts in controlling and regulating physiology of the fetus. Doppler ultrasound has become a part of routine antenatal care in monitoring such high-risk pregnancies. However, renal artery was the least studied.
Aim and objective: To compare the relationship of perinatal outcomes with renal artery Doppler and umbilical artery Doppler indices.
Materials and methods: A prospective observational study carried out among women attending an antenatal clinic and who have undergone delivery in Department of Obstetrics and Gynecology, in a tertiary care hospital between August 2016 and May 2018. Regular ultrasonography was done at 28–31 weeks; they were followed up 4 weeks later and Doppler indices were noted.
Results: In the 394 patients studied, 13.1% were having FGR, 12.2% were oligoamnios, and 12.2% had preterm delivery. The p values of the pulsatility index and the resistivity index of the renal artery in FGR, oligoamnios, preterm delivery, and low birth weight were more significant than umbilical artery Doppler indices.
Conclusion: Renal artery Doppler indices were significantly more reliable in predicting adverse perinatal outcomes in cases of mild uteroplacental insufficiency. Additionally, renal artery Doppler indices were able to pick up these changes earlier than umbilical artery Doppler, hence a potential early indicator, and the pulsatility index being more specific and sensitive.
Limitations: Sample size of the study is limited with only mild cases of FGR. Larger studies are required. In addition, patients at a higher risk of FGR in comparison with low-risk cases should be studied with more sample size as this study did not show any significant association with comorbidities.
Update on the diagnosis and classification of fetal growth restriction and proposal of a stage-based management protocol. Fetal Diagn Ther 2014;36(2):86–98. DOI: 10.1159/000357592.
Longitudinal changes in uterine, umbilical and fetal cerebral Doppler indices in late-onset small-for-gestational age fetuses. Ultrasound Obstet Gynecol 2011;37(2):191–195. DOI: 10.1002/uog.7738.
Doppler blood flow velocity waveforms in the fetal renal artery. Arch Gynecol Obstet 1989;246(3):133–137. DOI: 10.1007/BF00934074.
Fetal renal volume and renal artery Doppler in normal and intrauterine growth restricted fetuses. Egypt J Hosp Med 2018;73(3):6238–6242.
Normal values of pulsatility index front fetal vessels: a cross-sectional study on 1556 healthy fetuses. J Perinat Med-Offici J Wapm 1990;18(3):165–172. DOI: 10.1515/jpme.19188.8.131.52.
The renal-resistive index from the last 3 months of pregnancy to 6 months old. BJU Int 2001;87(6):562–564. DOI: 10.1046/j.1464-410X.2001.00085.x.
Doppler waveform patterns and reference ranges of fetal renal artery blood flow indices in normal Thai fetuses during the second trimester. Asian Biomed 2017;9(2):217–224.
Renal artery flow-velocity waveforms in normal and hypoxemic fetuses. Am J Obstet Gynecol 1989;161(1):168–172. DOI: 10.1016/0002-9378(89)90257-3.
Doppler ultrasonographic assessment of fetal renal artery blood flow velocity waveforms in intrauterine growth retarded fetuses. Kurume Med J 1992;39(3):203–208. DOI: 10.2739/kurumemedj.39.203.
Fetal renal artery velocity waveforms and amniotic fluid volume in growth-retarded and post-term fetuses. Obstet Gynecol 1991;77(3):370–373.
Fetal redistribution of blood flow and amniotic fluid volume in growth-retarded fetuses. Early Hum Dev 1997;47(3):297–304. DOI: 10.1016/S0378-3782(96)01798-7.
Evaluation of the renal artery in the fetuses with growth retardation and oligohydramnios by two dimensional Doppler ultrasonography. Nihon Sanka Fujinka Gakkai zasshi 1991;43(11):1554–1560.
Elevated renal tissue oxygenation in premature fetal growth restricted neonates: an observational study. PLoS ONE 2018;13(9):e0204268. DOI: 10.1371/journal.pone.0204268.
Changes in central and peripheral circulation in intrauterine growth-restricted fetuses at different stages of umbilical artery flow deterioration: new fetal cardiac and brain parameters. Gynecol Obstet Invest 2011;71(4):274–280. DOI: 10.1159/000323548.
Doppler velocimetry of the fetal middle cerebral and renal arteries: interobserver reliability. J Ultrasound Med 1996;15(4):317–2153. DOI: 10.7863/jum.19184.108.40.2067.
The role of resistance index in fetal renal artery in causing oligohydramnios among overdue pregnant women. Mustansiriya Medical Journal 2018;13(1):6.
Predictive value of fetal renal artery Doppler indices in idiopathic oligohydramnios and polyhydramnios. Menoufia Med J 2019;32(2):476. DOI: 10.4103/mmj.mmj_220_18.
Doppler study of the fetal renal artery in oligohydramnios with post-term pregnancy. J Med Ultrasound 2014;22(1):18–21. DOI: 10.1016/j.jmu.2013.10.005.
Longitudinal reference intervals for Doppler velocimetric parameters of the fetal renal artery correlated with amniotic fluid index among low-risk pregnancies. Int J Gynecol Obstet 2015;131(1):45–48. DOI: 10.1016/j.ijgo.2015.05.010.
Fetal renal blood flow velocimetry and cerebro-placental ratio in patients with isolated oligohydramnios. J Gynecol Obstetr Human Reproduc 2019;48(7):495–499. DOI: 10.1016/j.jogoh.2019.06.002.
Fetal renal artery impedance as assessed by Doppler ultrasound in pregnancies complicated by intraamniotic inflammation and preterm birth. Am J Obstet Gynecol 2009;200(2):203-e1. DOI: 10.1016/j.ajog.2008.11.001.
Fetal renal artery impedance in pregnancies affected by preeclampsia. J Perinat Med 2020(4):(ahead-of-print) 10.1515/jpm-2020-0024.