The Urine Stream Interruption Test and pelvic muscle function.

The Urine Stream Interruption Test (UST) was developed to assess the effectiveness of the pelvic floor muscles in impeding urine flow. In the present study, the repeatability of the UST and its relationship to other measures of pelvic muscle strength were tested. Seventy-five women (25 each nulliparous, primiparous, and secundiparous) were enrolled. Repeatability of the UST was demonstrated by a correlation of r = .83. Stronger pelvic muscle strength, as assessed by the Digital Measure, was correlated with more rapid interruption of the stream of urine, r = -.55 to -.59. Greater parity was associated with decreased ability to stop the flow, F = 10.2 [2, 72], p less than .001), with the UST scores longest in secundiparas (M = 4.4 seconds), next longest in primiparas (M = 3.6 seconds), and shortest in nulliparas (M = 1.96 seconds).