Dynamic assessment of pelvic floor and bony pelvis morphologic condition with the use of magnetic resonance imaging in a multiethnic, nulliparous, and healthy female population.

OBJECTIVE: The purpose of this study was to determine dynamic pelvic floor and bony pelvis morphologic condition in asymptomatic multiethnic women. STUDY
DESIGN: Pelvic floor anthropometry, at rest and after the Valsalva maneuver, and pelvimetry were compared with the use of magnetic resonance imaging in nulliparous young volunteers from 5 ethnic groups (n=11 x 5 volunteers: Emirati, other Arab, Filipino, Indian/Pakistani, and European/white volunteers), with the white volunteers as the reference group.
RESULTS: The white volunteers were significantly taller (P <.0001) than the other women. Their levator hiatus was significantly longer than the Emirati women (P=.03) and wider than the Filipino women (P=.04). The bladder neck descent on straining was also significantly greater than the other groups (P <.00001). The white women also had the longest transverse diameter of the pelvic inlet (P=.002). Their sagittal outlet diameter was significantly longer than the Emirati and Arab women (P=.02), and their interspinous diameter was significantly longer than the Arab women (P=.002).
CONCLUSION: Nulliparous, healthy white women have larger levator hiatus and bony pelvis with greater bladder neck descent on straining than non-white women.