Effects of menstrual cycle and urinary tract instrumentation on uroflowmetry

We sought to compare bladder emptying function in normal women during the p roliferative and secretory phases of the menstrual cycle and to evaluate wh ether urethral catheterization affected uroflowmetry parameters. Forty-nine normal volunteers (ages 19-42 years) were recruited and underwent uroflowm etry in the proliferative and secretory phases of the menstrual cycle. A se rum progesterone level of <3.0 ng/mL defined the proliferative phase. Durin g the proliferative phase, volunteers underwent uroflowmetry analysis when a sensation of fullness was appreciated. A post-void residual volume was de termined, and the bladder was filled with 400 mt of normal saline. Repeat u roflowmetry analysis was then performed. This two-step procedure was repeat ed at a separate visit during the secretory phase. Voided volume, residual volume, maximum and average flow rates, time-to-maximum flow, and duration of flow were recorded. Wilcoxon signed-rank tests were used for statistical analysis. A two-tailed a value of <0.05 defined statistical significance. Our analysis was limited to the 33 patients whose predicted menstrual datin g correlated with the obtained progesterone levels. During the follicular p hase, we found significantly faster maximum (P < 0.0001) and average flow r ates (P = 0.01), along with a shorter time-to-maximum flow (P < 0.0001) and shorter duration of flow (P < 0.0001), during the pre-catheterized void th an the post-catheterized void. Similar results were observed in the secreto ry phase with the exception of a slightly higher residual volume (P = 0.05) . No difference was seen in any measured uroflowmetry parameter when compar ing similar voids between phases of the menstrual cycle. We conclude that w hen evaluating pre-menopausal patients, uroflowmetry may be scheduled and p erformed during either phase of the menstrual cycle. (C) 2000 Wiley-Liss, I nc.