Pelvic Floor Disorders
Pelvic Organ Prolapse
Pelvic organ prolapse (POP) is a medical condition that develops when the pelvic floor fails to support the pelvic organs internally. As a consequence, the internal organs, including the bladder and urethra, vagina, uterus and cervix, as well as bowels, drop out through the vaginal opening, only to be covered by stretched vaginal walls. POP in women is very common, with approximately 300,000 operations for POP repair conducted in the USA alone on a yearly basis, resulting in one in nine women who will have POP repair surgery during her lifetime. Approximately a third will need to be reoperated on mostly owing to recurrence. There are many insults throughout a woman's life that can breach the integrity of the pelvic floor. Some of the pertinent ones are pregnancy and childbirth, aging, menopause, hypoestrogenism, genetic factors, race, trauma, smoking, pelvic surgery and medical conditions that put a chronic strain on the pelvic floor or cause nerve injury to the musculature of the pelvic floor (chronic coughing, being overweight, having an occupation that includes prolonged heavy lifting, genetic deposition and neurological disorders such as multiple sclerosis, stroke and Parkinson's disease). Of those risk factors, vaginal delivery has been most often determined as the culprit for initiating POP. Epidemiologic studies have demonstrated that women who have undergone multiple vaginal deliveries were more likely to develop prolapse compared with women who only had cesarean deliveries or were nulliparous. However, POP can develop earlier, during pregnancy, with the greatest changes noted in the third trimester, which also include bladder and urethral hypermobility. Evaluation with MRI and translabial/transperineal ultrasound has demonstrated that 20% of primiparous women end up with levator ani lacerations following vaginal childbirth[7,8].
Uterovaginal prolapse, or vaginal prolapse after a hysterectomy, is classified according to the wall or compartment that is prolapsed. Prolapse of the anterior wall is defined as a cystocele, prolapse of the posterior as a rectocele and when it includes a more proximal attenuation of the supportive connective tissue, which results in bowel herniation at the vaginal apex, this is considered an enterocele. Finally, prolapse of the cervix and uterus or vaginal apex (after a hysterectomy) is described as an apical prolapse.
There are several methods to quantify the degree of prolapse, which can be used to reproducibly document the degree of POP and which can allow longitudinal comparison of consecutive pelvic exams. The most accepted quantification system, now used both clinically and in pelvic floor research, is known as the Pelvic Organ Prolapse Quantification System (POPQ). Often, several compartments are prolapsed, which when moderate-to-advance, leads to symptoms such as the sensation of a 'bulge in the vagina', pelvic pressure and discomfort, and in some women, pelvic pain. A recent Swedish study showed that pelvic floor-related symptoms cannot be used to accurately predict the anatomic location of the prolapse in women with mild-to-moderate prolapse.
Urinary incontinence describes the involuntary loss of urine. The three main types of incontinence include stress urinary incontinence (SUI), urge urinary incontinence (UUI) and mixed incontinence which describes the presence of both types of urinary incontinence simultaneously. The cause of the incontinence is different for each subtype and involves difficulties with the innervation and musculature of the pelvic floor. Pregnancy and childbirth are strongly associated with SUI or UUI. As many as 32% of primiparous women may be affected by SUI. In the majority of affected women, the SUI resolves. In those who still have SUI 3 months postpartum there is a risk of 92% of having SUI at 5 years. Cesarean delivery after laboring does not protect from the development of SUI, implying that the process of laboring may be sufficient to adversely affect the integrity of the pelvic floor. As women age, other risk factors become more significant, such as obesity and aging. The association of UUI and vaginal delivery is not as well delineated. The prevalence of UUI after childbirth can be as high as 30% during the postpartum period.
Anal incontinence (AI) is classified as a PFD that results in flatus incontinence and/or the loss of formed, or loose stool that is bothersome. Obviously, AI results in adverse social and hygienic effects. Risk factors are similar to the development of POP, with pregnancy and childbirth cited as major culprits. Anatomically, the anal sphincter is composed of internal smooth and external striated muscles that surround the anal mucosa internally and the puborectalis muscle fibers externally. The anal sphincter complex stretches over a length of 3 cm proximally in the anal canal. The internal sphincter provides the majority of the resting tone of the anus, with the remaining 10% being provided by the external sphincter. The latter is responsible for the voluntary contraction of the anal canal. Many anal sphincter lacerations go unnoticed following pregnancy and childbirth, which could account for over 10% of women reporting AI without documented anal sphincter damage. Some studies suggest that pregnancy alone may be enough to impinge AI symptoms[19,20]. Repair of anal sphincter lacerations is not always successful in resolving AI and may impact quality of life and sexual function. A study on 86 women undergoing anal sphincteroplasty showed that, more than 5 years after the operation, only 11% were totally continent. However, there was no correlation between continence scores and sexual function.
Expert Rev of Obstet Gynecol. 2009;4(2):165-178. © 2009 Expert Reviews Ltd.
Cite this: Female Sexual Function and the Pelvic Floor - Medscape - Mar 01, 2009.