our knowledge of the immediate effects of parturition on pelvic floor
anatomy and physiology has been sparse. However, with the introduction
of computed tomography, ultrasonography, and magnetic resonance imagi
ng, new tools have become available for visualizing dynamic antenatal
and postpartum changes in the pelvic musculature. Although few studies
have been performed, there is evidence of a pregnancy-related increas
e in the frequency of urinary stress incontinence, and of an increased
frequency of persistent anal incontinence in cases of sphincter tears
.