Pelvic Organ Prolapse

Introduction

Pelvic organ prolapse (POP) is the herniation of pelvic organs through the urogenital diaphragm into the vagina or beyond. The urogenital diaphragm is the large muscle complex that comprises the pelvic floor. The tendency to develop prolapse and associated disorders is felt to be related to 2 factors: the changes in pelvic floor stresses during pregnancy produced by assuming the upright posture necessitating adaptation to a supportive role and the biomechanical changes associated with pregnancy itself as well as stresses associated with parturition. The resultant effects on the pelvic floor also contribute to the stress incontinence commonly associated with POP. It is estimated that POP is associated with stress urinary incontinence in 40% of cases. When there is loss of pelvic floor support, prolapse of the bladder, rectum, small bowel, or uterus may occur. Risk factors for prolapse include familial predisposition, obesity, hysterectomy, previous prolapse surgery, defective connective tissue, constipation/straining at stool, denervation and myopathy leading to a wide levator ani hiatus. Prolapse occurs most frequently in the anterior compartment and least frequently in the apical compartment, with posterior compartment prolapse in between.

Epidemiologic data regarding POP are based on relatively small numbers of subjects and global data is lacking. It is widely suspected that incidence and prevalence are underreported. In one U.S. study, the lifetime risk of undergoing a single operation for prolapse or incontinence by age 80 was 11.1%. The prevalence of POP based on the sensation of a genital mass or bulge ranges from 5-10%. Most studies suggest that black women have the least POP, while white and Hispanic women have the highest prevalence. Additionally, a recent study determined that Asian women also have a significantly higher risk of developing POP.

Symptoms

The most common complaint of women with POP is a feeling of a bulge or heaviness in their genital area. Other clinical features of POP may include a dragging feeling in the pelvis, urinary incontinence, difficulties with passage of urine or stool (requiring digital splinting to aid in urination and/or evacuation), defaecatory dysfunction including flatus and/or faecal incontinence, tenesmus, constipation, sexual dysfunction and chronic pelvic pain.

Urinary incontinence associated with POP can be overt or occult.

Overt incontinence means that the patient is symptomatic: POP is present and the patient complains of stress, or mixed stress and urge incontinence. On physical examination, the stress test is positive; that is, cough or Valsalva strain results in urinary incontinence.

Occult incontinence may also be referred to as masked or latent incontinence: POP is present and the patient does not complain of urinary incontinence, or she recalls a period of stress urinary incontinence that spontaneously disappeared. During physical examination, there is no visible stress incontinence when the prolapse is manifest, but after reduction of the prolapse, the stress test becomes positive, resulting in incontinence. It is very important that patients be evaluated for occult incontinence so that ultimate repair of the prolapse will consider inclusion of an anti-incontinence procedure.

Assessment

In recent years, descriptive terminology (cystocele, rectocele, enterocele) naming the anatomical structure that is believed to be prolapsed has been discouraged because it may be difficult to precisely discern on physical exam. The ICS Pelvic Organ Prolapse Quantification (POPQ) examination is preferentially used to define prolapse based on the observed descensus of various portions of the reproductive tract during Valsalva strain with respect to a fixed point, the hymen. It may be beneficial to examine a patient in the supine and standing positions to reproduce her symptoms and to optimally assess the pelvic floor defects and incontinence.

Treatment

Conservative therapies for POP include pelvic floor muscle training as first line therapy, which improves symptoms and is best for mild degrees of prolapse and pessaries. Pessaries are devices that come in various shapes and sizes. They are inserted into the vaginal vault in such a way as to prevent descent of the prolapsing tissue. There are also pessaries for stress incontinence alone. These devices are often used in conjunction with vaginal estrogen to prevent erosion of the vaginal wall. Pessaries are most often used in the elderly or patients who are surgery-averse.

Definitive treatment of POP involves surgical repair. Surgical intervention for POP has as its goal the restoration of normal vaginal anatomy while maintaining normal excretory and sexual function. Repairs may be performed transvaginally or transabdominally using an open or laparoscopic approach. Combined abdominal and vaginal approaches are also used. Concomitant hysterectomy may be necessary to accomplish repair. The abdominosacrocolpopexy, suspending the vaginal vault to the sacrum, is considered the gold standard and has about a 90 % success rate.

A recent Cochrane Review suggested abdominal sacral colpopexy is superior to vaginal sacrospinous fixation for uterine or vaginal prolapse. Transvaginal repairs of rectal prolapse appear to be better than a transanal approach. Further, the use of biological or synthetic graft material reduces the recurrence of POP.

Conclusion

POP is a highly prevalent condition that can result in severely compromised quality of life, particularly when it exists in advanced stages. Conservative therapy largely consists of the use of pessaries to reduce the prolapse and more recently the benefits of pelvic floor muscle training have been evidenced, but surgical intervention is definitive. Often, an anti-incontinence procedure must be done in conjunction with pelvic floor reconstruction in order to prevent de novo stress incontinence.

Selected References

1. Haylen BT, de Ridder D, Freeman RM, et al. An International Urogynecological Association (IUGA)/International Continence Society (ICS) joint report on the terminology for female pelvic floor dysfunction. Neurourol Urodyn. 2010; 29(1):4-20.
2. Olsen, A. L., Smith, V. J., Bergstrom, J. O., et al : Epidemiology of surgically managed pelvic organ prolapse and urinary incontinence. Obstet Gynecol, 1997; 89(4):501-6.
3. Bump RC, Mattiasson A, Bo K, et al. The standardization of terminology of female pelvic organ prolapse and pelvic floor dysfunction. Am J Obstet Gynecol. 1996 Jul; 175(1):10-7.
4. Sears CL, Wright J, O’Brien J, et al. The racial distribution of female pelvic floor disorders in an equal access health care system. J Urol. 2009 Jan; 181(1):187-92.
5. Sewell CA, Chang E, Sultana CJ. Prevalence of genital prolapse in 3 ethnic groups. J Reprod Med. 2007 Sep; 52(9):769-73.
6. Whitcomb EL, Rortveit G, Brown JS, et al. Racial differences in pelvic organ prolapse. Obstet Gynecol. 2009 Dec; 114(6):1271-7.
7. Reena C, Kekre AN, Kekre N. Occult stress incontinence in women with pelvic organ prolapse. Int J Gynaecol Obstet. 2007 Apr;97(1):31-4.
8. Brækken IH, Majida M, Engh ME, Bø K. Can pelvic floor muscle training reverse pelvic organ prolapse and reduce prolapse symptoms? An assessor-blinded, randomized, controlled trial. Am J Obstet Gynecol. 2010; 203(2): 170e1–7.
9. Hagen S, Stark D, Glazener C , Sinclair L, Wilson D, Norrie J, Dickson S, McPherson G, Logan J, Frawley H, Moore KH, Walker A. A multicentre randomised controlled trial of a pelvic floor muscle training intervention for women with pelvic organ prolapse. Neurourol. Urodynam. 2011;30(6):983-984.
10. Maher C, Feiner B, Baessler K, Schmid C. Surgical management of pelvic organ prolapse in women. Cochrane Database Syst Rev. 2013 Apr 30;4:CD004014. Review.