Objective: There is little information available on what constitutes "normal" pelvic organ mobility. This study presents normal values for urethral, bladder, cervical, and rectal descent on Valsalva.
Study design: One hundred eighteen nulligravid white women aged 18 to 24 years were recruited for a prospective observational study. Translabial ultrasound was undertaken supine and after voiding, with the most effective of at least 3 Valsalva maneuvers used for evaluation.
Results: Urethral rotation on Valsalva varied from 0 to +90 degrees (mean 32 degrees), bladder neck descent from 1.2 to 40.2 mm (mean 17.4 mm). The cervix descended to between 59 and 0 mm above the symphysis pubis (mean 30.8 mm); the rectal ampulla descended to between 54 mm above and 22 mm below the symphyseal margin (mean 7.8 mm). In a test-retest series, intraclass correlations were between 0.64 and 0.89, implying good-to-excellent repeatability of the ultrasound assessment.
Conclusion: A wide range of values was obtained for all parameters. A significant congenital contribution to the phenotype of female pelvic organ prolapse appears likely.