Ultrasonographic detection of ureteral jets in normal pregnancy

Our purpose was to determine the impact of normal physiologic urodynamic alterations of pregnancy on the detection of ureteral jets into the bladder with use of transabdominal color Doppler ultrasonography.

We conducted a prospective cohort study of 125 healthy asymptomatic gravid women without any history of past or current renal disease, all with singleton pregnancies between 13.4 and 37.7 weeks' gestation. Right and left ureteral jets were recorded over a 5-minute period with use of color Doppler transabdominal ultrasonography and a full bladder. Each kidney was graded by the severity of the hydronephrosis. No hydronephrosis was grade 0, mild hydronephrosis was grade 1, and moderate hydronephrosis was grade 2. There were no cases of severe hydronephrosis.

There were 56 grade 0 cases on the right versus 93 grade 0 cases on the left (p < 0.0001), 53 versus 30 grade 1 cases (right vs left, p < 0.003) and 16 versus 2 grade 2 cases (right vs left, p < 0.0009). In the subgroup where both kidneys were grade 0 the mean number of right ureteral jets 5 mm was 14.7 versus 15.1 for the left ureteral jets (p = 0.73). In the grade 1 subgroup mean right versus left ureteral jets was 15.4 versus 16.6 (p = 0.65). For the grade 2 subgroup mean right versus left ureteral jets was 15.5 versus 21.0 (p = 0.32). There were 4 of 125 unilateral absent ureteral jets on the right versus 0 of 125 on the left (p = 0.122).

Our data demonstrate that ureteral jets can be readily detected during pregnancy independent of the gestational age. In addition, it does not appear that the physiologic urodynamic alterations of pregnancy affect the frequency or symmetry of ureteral jets. Thus identification of ureteral jets can be used in the workup of suspected urolithiasis in pregnant patients.