Two surgeries for pelvic prolapse found similarly effective, safe

RESEARCH TRIANGLE PARK, N.C. — Two surgical procedures to treat a form of pelvic hernia affecting women have similar rates of success and safety, according to researchers who conducted a National Institutes of Health study. The study also found that a guided exercise therapy to strengthen pelvic muscles did not add to the benefits of either surgery.

The study, published in the Journal of the American Medical Association, was conducted by the National Institute of Child Health and Human Development Pelvic Floor Disorders Network and led by the Cleveland Clinic. RTI International is the data coordinating center for the network and co-author of the study. 

Surgical procedures and exercise therapy are used to treat pelvic organ prolapse, an often uncomfortable and sometimes painful weakening of the pelvic organs that may affect women in the years after childbirth. Previous network research suggests that about three percent of U.S. women will have symptoms of prolapse in a given year, and that the condition is especially common in older women and women who have given birth several times. Nearly 300,000 women undergo surgery for prolapse each year in the United States.

Normally, a sling of muscle and tissue spans the bottom of the pelvic cavity, holding the bladder, uterus, and other organs in place.  In pelvic organ prolapse, this sling weakens, and the internal organs slump downward, pressing on the vagina and anus.  In some cases, the pressure causes the vagina to invert and protrude through the vaginal opening. Symptoms may also include urinary or fecal incontinence and pelvic pain.

In two of the most common surgeries for pelvic organ prolapse, surgeons stitch the top of the vagina to ligaments inside the pelvic cavity.  One procedure, uterosacral ligament suspension, involves stitching the vagina to the uterosacral ligaments, which normally connect the lower part of the womb to the tailbone.  The other procedure, sacrospinous ligament fixation, involves stitching the top of the vagina to one of two sacrospinous ligaments, which link the lower tailbone to the pelvis.

Many women who undergo surgery for pelvic organ prolapse also receive one-on-one sessions with a specialized physical therapist or nurse who coaches them on exercises meant to strengthen the pelvic floor muscles.

Of the 374 women who took part in the study, 188 were assigned randomly to undergo uterosacral ligament suspension, and 186 were randomized to receive sacrospinous ligament fixation.  In addition, half of the women receiving either of the two surgical treatments were further randomized to a guided exercise course to strengthen the pelvic muscles or to usual care (self-care instructions from the surgeon but no exercise course). The exercise course consisted of one pre-surgical session and four sessions in the 12 weeks after the surgery. These participants were coached on muscle-contraction exercises that targeted their weakest pelvic floor muscles.

After two years, the researchers evaluated the success of the surgical procedures and exercise course. The researchers judged success according to a scoring system that accounted for physician observations during a gynecological examination and the women's responses to questions about their symptoms. The scoring system took into account the extent to which the top of the vagina protruded into the vaginal canal, the need for follow-up surgery to treat the prolapse or urinary incontinence, and the women's experience of painful or bothersome sensations in the pelvic area.

After two years, there was no statistically significant difference in the success rates of the two types of surgery. Of the women undergoing uterosacral ligament suspension, 59.2 percent received a score indicating success. For women undergoing sacrospinous ligament fixation, 60.5 percent received a score in the successful range. 

According to the study authors, compared to previous studies of these surgeries, these reported rates of success are relatively low. However, this study used stricter criteria for defining success than other studies have. In fact, only about five percent of all women in this study received follow-up prolapse surgery or a vaginal-support device in the two years after their surgery.

In both surgical groups, the women experienced similarly low rates of serious adverse outcomes, with less than five percent having a serious adverse event directly related to the procedure.

The guided exercise program did not seem to offer additional benefit to most of the participants. Within both surgical groups, scores on measures of incontinence, prolapse and discomfort did not vary significantly between women in the exercise program and those who received usual care only.  

In addition to the Cleveland Clinic and RTI, co-authors of the study include researchers from the University of Alabama at Birmingham; Loyola University Chicago Stritch School of Medicine; University of Utah Medical Center; Duke University Medical Center; Southern California Kaiser Permanente; University of California-San Diego Health Systems; University of Texas-Southwestern Medical Center; Duquesne University; University of Michigan; and Eunice Kennedy Shriver National Institute of Child Health and Human Development for the NICHD Pelvic Floor Disorders Network.

The NIH Office of Research on Women’s Health providing funding for the study, in addition to support from the National Institute of Child Health and Human Development.