The pelvic organs are kept in place by the muscles and connective tissues of the pelvis (pelvic diaphragm). The vagina of an adult woman is normally a round-topped, muscular tube that also supports the other pelvic organs. The pelvic muscles and tissues can be stretched or damaged, most commonly by childbirth. When they don't recover, they lose their ability to support the organs.

The location and severity of pelvic organ prolapse is related to where in the pelvis the injury or muscular damage has occurred. You may have several areas of injury that contribute to prolapse. Prolapse may occur after surgery to remove the uterus (hysterectomy) if the procedure removes or damages support of the bladder, urethra, or bowel wall. If other conditions, such as childbirth, damage muscles or nerves in the pelvis, the pelvic diaphragm may lose its dome shape, become more like a funnel, and then bulge down into or out of the vagina. A prolapse may occur when nerves that control the pelvic structures are damaged, as might happen if the nerves of the vagina are injured during labor by the movement of the baby through the birth canal. ²

Pelvic organ prolapse may increase pressure on the vagina and interfere with sexual activity, sometimes leading to sexual dysfunction. For more information, see the topic Sexual Problems in Women.

Lower estrogen levels during and after menopause make pelvic organ prolapse more likely. Estrogen helps your body to make collagen, a protein that enables the supportive tissues of the pelvis to stretch and return to their normal positions. Less collagen makes it more likely that those supportive tissues will tear. When estrogen levels go down, so do collagen levels. A lower level of collagen may lead to the involuntary release of urine (urinary incontinence). For more information, see the topic Urinary Incontinence in Women.

Pelvic organ prolapse may be a progressive condition, gradually getting worse and causing more severe symptoms. However, in many cases it does not progress and may improve over time.³