[Ultrasonography of pregnancy-induced dilatation of maternal kidney calices in a normal patient sample].

To examine the physiological changes of the calyceal system during pregnancy, we selected a normal group of 187 pregnant women by anamnestic, clinical, ultrasonic and laboratory findings. The sonographic investigation of renal pelvis, renal calyces and ureters revealed a more frequent and more pronounced dilatation of the right side. The dilatation was more marked as expected by literature. The complete involution post partum occurred mostly during the first ten days. Even after marked dilatations, a parenchymal reduction could not be found.