Kidney impairment in fetal growth restriction: three-dimensional evaluation of volume and vascularization.

Abstract

Renal development is impaired in fetal growth restriction (FGR). Renal size can be considered a surrogate of renal function in childhood, and could be impaired in that condition. Our aim was to evaluate the ratio of total renal volume, measured by three-dimensional ultrasound, to estimated fetal weight (TRV/EFW) among fetuses with and without growth restriction. Furthermore, we correlated TRV/EFW with fetal Doppler velocimetry and renal vascularization indexes and evaluated the association of renal volume and vascular parameters with adverse neonatal events in growth-restricted fetuses. In a retrospective cohort, TRV and renal vascularization of growth-restricted and normal fetuses were evaluated by three-dimensional ultrasonography and VOCAL technique. Independent samples t-tests and Mann-Whitney test were used for comparisons between groups. Logistic regression model was applied to evaluate the association between renal characteristics and adverse neonatal events. Seventy-one growth-restricted fetuses were compared to 194 controls. The TRV/EFW was lower in the growth-restricted group (P < .001). In our sample, this ratio did not correlate with Doppler velocimetry parameters, renal vascular indexes or any adverse neonatal events. The TRV/EFW ratio is decreased in FGR. Further studies are needed to investigate the association of this ratio with long-term renal outcomes.