[Ultrasonic biometry of the fetal kidney]

Renal biometry of the fetus was carried out on 1200 women when exogenous difference between renal and surrounding tissue became distinct. Three dimensions of the kidney were measured at two mutually performed perpendicular scans. In our study it was established that the ratio between the circumference of the kidney and the abdominal circumference was a constant, preserving itself during the whole pregnancy. Establishment of this process presented diagnostic criteria for fetal hypotrophy as well as for anomalies in the development of the kidney. The three parameters as well as the estimated by them volume of the kidney could be presented as dynamic curves, rather similar in their course with the curves of BPD and the abdominal circumference. Prognosis of the fetal weight was made on the basis of the volume of the kidney by the formula W = 125, 1689 + (0.2008 X V), as the exactness of the method was commensurable with the precision of the popular combined biometric formulas, although only one parameter was used. The ratio the pelvis:kidney was of interest as well, since it differed from that of the grown up persons and it was from 1:3 to 1:4 within the fetal norm. The transverse size of pelvis at least over 15 mm suggested obstructive uropathy and hydronephrosis. There was no statistically significant difference in the biometric parameters of the right and left kidney of the fetus in our study.