The relevance of parity to ureteric dilatation

To assess whether the mild dilatation of the right ureter in women that is sometimes seen on intravenous urography (IVU) represents persistent dilatation after a previous pregnancy.

The intravenous urograms of 71 men, 63 parous and 27 nulliparous women were evaluated prospectively. The two groups of women were divided into those with and without a confirmed history of urinary tract infection (UTI) as the indication for IVU. producing five groups in all. Measurements were taken on both the 5-min and the compressed or release films on each side.

There were no significant differences in ureteric diameters among the five groups for the uncompressed right ureter (P=0.23), the left ureter uncompressed (P=0.32) or compressed (P=0.87). For the compressed right ureter, the difference was significant, with the diameters in the parous women with proven UTIs being larger than in the other groups (P=0.043).

There is a significant increase in the diameter of the compressed right ureter in the group of parous women with a history of proven UTI. Infection or parity alone do not produce this effect: the combination of the two factors is required.