Current concepts of female pelvic anatomy and physiology.

The female urinary bladder and urethra are situated on the intrapelvic surface of the anterior vaginal wall, firmly anchored to the distal vagina by the urogenital diaphragm and to the superior vagina at the vesicocervicouterine junction. The anterior surface of the proximal urethra is firmly anchored to the posterior aspect of the symphysis pubis by the pubourethral ligaments and to the remaining distal vagina by the lower two thirds of the urogenital diaphragm. The lateral bladder wall derives its support from the anterior vaginal wall attachments to the pelvic sidewall. The anterior vaginal wall is strongly supported by pubococcygeus muscle fibers inserting on the vaginal wall and the genital hiatus and by the cardinal and uterosacral ligaments. Vaginal detachment from the lateral pelvic sidewall can result in herniation, with accompanying secondary posterior bladder descent. Levator ani weakness or injury may be a contributing etiologic factor in the genesis of vaginal wall detachment and the development of stress incontinence.