Do posture and straining influence urinary-flow parameters in normal women?

The influence of posture of the pelvis and straining on urinary flow was in vestigated in 21 normal women, mainly physiotherapists, who were asked to u rinate on an uro-flow chair at their usual time and frequency. Subjects wer e at random instructed to urinate in five different test situations: anteve rsion, anteversion with straining, retroversion, retroversion with strainin g, and forward bending without straining; The urinary-flow parameters inves tigated were volume, peak flow, time to peak, peak-to-end time, total time, and mean flow. The analysis was done by means of analysis of variance but only for micturition volumes >150 mt. The morphology of the urinary-flow cu rves was examined for the presence of irregularities and increasing (after top) or decreasing (for top) curve tops and after-dribbling. Results demons trated no significant differences for peak flow, total time, and mean flow in the anteversion, retroversion, and the forward-bending position. This ho lds for test situations and re-test controls. However, straining increased the peak flow and mean flow rates in all positions and in all women, wherea s it reduced the total voiding time. The voided volumes were lowest in ante version. Irregularities were less frequent in the forward-bending position. It can be concluded that the forward-bending position is the most preferab le urinating position to relax the pelvic floor muscles. (C) 2000 Wiley-Lis s, Inc.