Female stress urinary incontinence: Choosing a primary surgical procedure

INTRODUCTION — Stress urinary incontinence (SUI), the involuntary leakage of urine on effort or exertion, or on sneezing or coughing, affects 4 to 35 percent of women [1-3]. Conservative approaches to treatment of SUI include pelvic floor muscle training and incontinence pessaries. However, for women who decline or have insufficient improvement following conservative therapy, there are a variety of surgical treatments. The introduction of midurethral slings (MUS) has changed the decision process for surgical treatment and is likely a factor in the increase in the rate of anti-incontinence surgery in the United States from 0.8 of 1000 women in 1979 to 1 of 1000 in 2006 [4-6].

The process of choosing a surgical procedure for women with SUI who have not had a prior anti-incontinence surgery will be reviewed here. Choosing a type of MUS, nonsurgical management of SUI, treatment of recurrent SUI, and diagnosis and treatment of other types of urinary incontinence are discussed separately.

●(See "Female urinary incontinence: Evaluation".)

●(See "Female urinary incontinence: Treatment".)

●(See "Surgical management of stress urinary incontinence in females: Choosing a type of midurethral sling".)

●(See "Stress urinary incontinence in females: Persistent/recurrent symptoms after surgical treatment".)

In this topic, when discussing study results, we will use the terms "woman/en" or "patient(s)" as they are used in the studies presented. However, we recognize that not all genetic females identify as women, and we encourage the reader to consider the specific counseling and treatment needs of transgender and gender diverse individuals.

TERMINOLOGY — Terminology used throughout this topic review is defined here (table 1):

●Stress urinary incontinence (SUI) – Involuntary leakage of urine on effort or exertion, or on sneezing or coughing [1].

●Suburethral sling – A suburethral sling is a sling that is inserted through a small vaginal incision and placed either at the bladder neck, midurethra, or proximal urethra for the purpose of supporting the urethra in women with SUI. This category includes both bladder neck and midurethral slings (MUS).

•Pubovaginal sling – A suburethral sling that is placed at the level of the proximal urethra and bladder neck (figure 1). This procedure is usually performed using both a vaginal and abdominal incision. These slings can be made of either biologic materials (including the patient's own tissue) or synthetic mesh. (See "Surgical management of stress urinary incontinence in females: Pubovaginal sling procedures".)

Bladder neck slings are also referred to as proximal urethral slings. They are referred to as pubovaginal slings when the arms of the sling material are affixed to the anterior rectus fascia rather than the pubic bone or Cooper's ligament [7].

•Midurethral sling – A suburethral sling that is inserted via a small vaginal incision and placed at the level of the midurethra in a tension-free manner (eg, tension-free vaginal tape procedures). These slings are made of synthetic mesh and can be placed in a retropubic or transobturator fashion. (See "Surgical management of stress urinary incontinence in females: Choosing a type of midurethral sling".)

●Retropubic colposuspension – Procedures performed through laparotomy or laparoscopy (Burch, Marshall-Marchetti-Krantz [MMK]) in which the vaginal wall adjacent to the midurethra and bladder neck is suspended, using sutures, in a retropubic position (figure 2A-C). These procedures are also referred to as retropubic urethropexy. (See 'Abdominal approach' below.)

CANDIDATES FOR SURGICAL TREATMENT — Women who are planning primary surgical treatment of stress urinary incontinence (SUI) should undergo preoperative evaluation to reasonably exclude other etiologies of urinary incontinence and assess surgical risk. (See "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure".)

Women who decline or have persistent symptoms following conservative therapy — In general, a trial of conservative therapy is advisable prior to surgical treatment because of its low-risk profile [8]. Conservative therapy for SUI includes pelvic muscle exercises (PME) with or without biofeedback or incontinence pessaries (see "Female urinary incontinence: Treatment"). However, some women ultimately need surgical intervention despite such conservative measures. In one study of 198 women treated with PME for SUI, women with severe stress incontinence, age <55 years, and higher educational level were more likely to go on to surgical treatment within 12 months of PME [9].

For SUI, surgical treatments have consistently demonstrated higher efficacy rates than conservative therapy (eg, approximately 40 percent for PME versus 70 to 80 percent for surgery) [10-13]. As an example, in the only randomized trial to compare surgical and conservative therapy for SUI, midurethral sling (MUS) surgery compared with physiotherapy had a significantly higher subjective improvement rate (90.8 versus 64.4 percent) and objective cure rate (76.5 versus 58.8 percent) at 12-month follow-up [12]. However, SUI surgery is associated with increased morbidity, postoperative voiding difficulty, and development or worsening of urgency incontinence. Thus, surgical intervention is often reserved for those with persistent symptoms despite conservative therapy.

The minimum evaluation before primary MUS surgery in women with SUI includes: (1) history, (2) urinalysis, (3) physical examination, (4) demonstration of SUI, and (5) measurement of postvoid residual urine volume [8]. (See "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure".)

Women with mixed urinary incontinence (components of both stress and urgency incontinence) may benefit from oral medication if urgency symptoms are the more bothersome component. Reduction of urgency symptoms may help the patient sufficiently to avoid surgery for the concomitant stress incontinence symptoms. (See 'Mixed incontinence' below and "Female urinary incontinence: Treatment", section on 'Pelvic floor muscle (Kegel) exercises'.)

Women with occult SUI — Advanced pelvic organ prolapse (POP) and SUI commonly co-exist; however, in many women, the SUI may become apparent only when the prolapse has been corrected. This phenomenon is known as occult SUI and is not reliably predicted by only using preoperative urodynamic testing with prolapse reduction. Concomitant anti-incontinence surgery is warranted in some women who are undergoing repair of advanced POP. This topic is discussed separately. (See "Pelvic organ prolapse and stress urinary incontinence in females: Surgical treatment", section on 'Symptomatic POP without symptomatic SUI'.)

Women finished with childbearing — Since pelvic support may be disrupted during pregnancy, and particularly following a vaginal birth, most clinicians recommend delaying surgical management of SUI until childbearing has been completed. However, it is not clear if subsequent delivery or mode of delivery (vaginal or cesarean) impacts future SUI risk. In a population-based cohort study that compared the risk of SUI in individuals with prior MUS surgery who did or did not have a subsequent delivery, researchers were unable to demonstrate statistically different rates of SUI between the two groups (odds ratio [OR] 1.2, 95% CI 0.7-2.0) [14]. Vaginal and cesarean delivery modes were not statistically associated with risk of SUI (22 versus 22 percent, OR 0.6, 95% CI 0.2-1.4), and there were no statistically significant differences in Urogenital Distress Inventory and Incontinence Impact Questionnaire scores between any of the groups. However, long-term data from larger and prospective samples are lacking. We counsel women of childbearing age who elect surgical treatment on the minimal data regarding the preferred mode of delivery and the risk of recurrent incontinence following delivery [14-16].

TYPES OF PROCEDURES — The prevailing evidence supports using a vaginal approach for anti-incontinence procedures.

Vaginal approach

●Midurethral sling (MUS)

●Bladder neck sling

●Injection of urethral bulking agents

Currently, bladder neck slings are mainly reserved for women in whom MUS are contraindicated or were unsuccessful. This is largely due to the decrease in morbidity and less voiding dysfunction associated with performing MUS (see 'Comparison of efficacy' below). Conditions in which autologous fascia sling in women may be considered include:

●Patients who decline synthetic materials.

●Patients with severe stress urinary incontinence (SUI) and a nonmobile, fixed urethra.

●Autologous fascia sling may be preferable to an MUS due to its slightly more obstructive nature. Women undergoing urethral reconstruction (eg, diverticulectomy or fistula repair) are considered for concomitant autologous fascial bladder neck slings. Several investigators reported good incontinence outcomes and low complication rates after urethral diverticulectomy and autologous fascial sling [17,18].

●Women who have had complications from prior mesh placed in the anterior vagina (for sling or prolapse) may be candidates for autologous fascia sling. Several case series report good outcomes with removal of prior mesh and placement of autologous fascia sling [19,20].

The use of urethral injectable agents is often reserved for women who are unable to tolerate, or wish to defer, surgery. In addition, these agents are used in some patients with recurrent or refractory incontinence after a prior incontinence procedure. (See 'Lack of urethral hypermobility and intrinsic sphincter deficiency' below and 'Older, frail, or medically complex individuals' below.)

Abdominal approach — The modified Burch retropubic colposuspension (described by Tanagho, also referred to as Burch or retropubic urethropexy) can be performed via laparotomy/mini-laparotomy, conventional laparoscopy, or robot-assisted laparoscopy [21].

Artificial urinary sphincter — Artificial urinary sphincter placement is rarely used in women but has been reported in several small case series [22-25]. The procedure can be performed using a vaginal, transabdominal, or laparoscopic route for women with SUI and intrinsic sphincter deficiency that is refractory to other common treatments. In this procedure, the Space of Retzius is entered, incisions are made lateral to the bladder neck and the urethra is dissected. An artificial urinary sphincter is circumferentially wrapped around the bladder neck and a fluid-filled balloon reservoir is left in the Space of Retzius. In one of the largest series, 52 women with intrinsic sphincter deficiency underwent laparoscopic artificial urinary sphincter implantation [22]. After a median follow-up of 24 months, 78 percent of women were continent and 16 percent reported improved continence. However, revision of the artificial sphincter was needed in 22 percent of women, including seven patients who required a repeat sphincter placement and four who required permanent removal. Based on the invasive surgery and high revision rate, this procedure is not a first-line therapy.

Procedures no longer recommended — Surgical treatment of SUI has evolved, particularly since the introduction of MUS. Several procedures that were once widely used are now no longer recommended since there are more effective alternatives. Data regarding these procedures will be reviewed in this section. Choosing among procedures that are currently in use is discussed below. (See 'Choosing a procedure' below.)

Retropubic colposuspension has generally been used as the reference standard for these procedures. This is because the procedures in this section precede the widespread use of suburethral slings, particularly MUS. Thus, they can be compared with slings only indirectly, using data that show that the efficacy of midurethral sling placement is comparable to colposuspension. (See 'Comparison of efficacy' below.)

Anterior colporrhaphy — Anterior colporrhaphy (even with Kelly-Kennedy plication) is not an effective approach to surgical treatment of SUI [26,27]. A meta-analysis of eight randomized trials found that the SUI treatment failure rate within one to five years was significantly higher after anterior repair compared with retropubic colposuspension (38 versus 17 percent, risk ratio [RR] 2.3, 95% CI 1.7-3.1) [28]. No difference was found in perioperative complications between the two procedure types.

Paravaginal repair — Transabdominal paravaginal repair is also ineffective as a treatment for SUI. There are few high-quality data regarding use of paravaginal repair for women with SUI. A small, randomized trial (n = 36) found that the success rate at one to three years was significantly lower following paravaginal repair compared with Burch colposuspension (72 versus 100 percent) [29]. No difference was found in perioperative complications between the two procedures. In addition, observational studies have reported that paravaginal repair for treatment of SUI was associated with a 20 to 57 percent failure rate [30,31].

Transvaginal needle suspensions — Transvaginal needle suspensions (eg, Raz, Stamey, or Gittes procedures) have largely been replaced by other procedures. These procedures are also referred to as needle urethropexy and consist of transvaginal placement of permanent sutures to attach the suburethral endopelvic fascia to the rectus fascia or pubic bone. A meta-analysis of 10 trials demonstrated a significantly higher SUI treatment failure rate at one-year postoperatively for needle suspension compared with retropubic colposuspension (29 versus 16 percent, RR 2.0, 95% CI 1.5-2.7) [32]. No statistical difference was found in the rate of perioperative complications between the two procedure types.

Marshall-Marchetti-Krantz — The Marshall-Marchetti-Krantz (MMK) procedure, a type of retropubic colposuspension that has generally been an alternative to Burch colposuspension, is rarely used. The two procedures vary by the site of attachment of the endopelvic fascia:

●In the Burch procedure, the endopelvic fascia adjacent to the mid and proximal urethra at the bladder neck is attached to the pectineal (Cooper's) ligaments on the posterior surface of the superior pubic ramus (figure 2A-C).

●In the MMK procedure, the endopelvic fascia next to the bladder neck is attached to the periosteum of the posterior pubic symphysis (figure 3).

Burch appears to be more effective than MMK and also has a lower procedural morbidity. A meta-analysis of four randomized trials found that, at one- to five-year follow-up, the SUI treatment failure rate was significantly lower for Burch compared with MMK (23 versus 34 percent, RR 0.72, 95% CI 0.52-0.99) [33]. However, Burch has additional advantages compared with MMK, including: (1) duration of postoperative bladder catheterization is an average of six days shorter with Burch; (2) osteitis pubis occurs after 1 percent of MMK procedures, but not after Burch; (3) the pectineal ligament is a stronger supporting structure than the pubic periosteum; and (4) Burch corrects small anterior wall support defects [32,34,35].

CHOOSING A PROCEDURE

Comparison of efficacy — We recommend midurethral sling (MUS) surgery for most healthy women with stress urinary incontinence (SUI) who desire surgical treatment; MUS have comparable to superior efficacy compared with other procedures, shorter operative duration and recovery times, and lower rates of repeat incontinence surgery [13,36,37]. One disadvantage of both retropubic and transobturator MUS is the higher risk of bladder perforation compared with other incontinence surgeries, but which is typically easily managed. The rate of bladder injury is higher for retropubic than transobturator MUS. In addition, risk of subsequent mesh-related complication is inherent in the insertion of synthetic mesh.

●(See "Surgical management of stress urinary incontinence in females: Choosing a type of midurethral sling".)

●(See "Transvaginal synthetic mesh: Complications and risk factors", section on 'Complications by procedure'.)

Since the introduction of the first retropubic MUS in the 1990s, these procedures have become the procedure of choice for primary surgical treatment of SUI because they are highly effective for both symptom cure and improvement and have relatively low rates of adverse effects compared with bladder neck sling or open procedures [13,36,38-42]. A network meta-analysis of over 21,000 women from 175 trials, obtained from earlier meta-analyses and subsequent trials, reported SUI cure rates of 89.4 percent for traditional bladder neck sling, 89.1 percent for retropubic MUS, 76.6 percent for open colposuspension, and 64.1 percent for transobturator MUS [36]. Compared with retropubic MUS, the odds of symptom resolution were: bladder neck sling odds ratio (OR) 1.06, 95% credible interval 0.62-1.85; open colposuspension OR 0.85, 95% credible interval 0.54-1.33; and transobturator MUS 0.74, 95% credible interval 0.59-0.92. Trial data mainly included assessments at or near 12 months. When MUS was used as the comparator for symptom improvement, the procedures associated with the next highest odds of improvement were transobturator MUS, traditional bladder neck sling, and open colposuspension. Symptom cure and symptom improvement were defined as resolution of incontinence and any improvement in incontinence from baseline, including cure, respectively. In comparisons of the two common MUS types, retropubic MUS were associated with more vascular complications, bladder and/or urethra perforations, and voiding difficulties (including urinary retention) compared with transobturator MUS. Transobturator MUS was associated with higher rates of repeat incontinence procedures and groin pain. These findings from the largest analysis to date were similar to previously published outcomes [13,40,41]. A major limitation of the network meta-analysis is the relatively short period of follow-up in most of the trial data. Detailed reviews of retropubic, transobturator, and the modified single incision slings are presented separately. (See "Surgical management of stress urinary incontinence in females: Choosing a type of midurethral sling".)

In trials that assessed efficacy over longer time periods, retropubic MUS efficacy was comparable to open colposuspension in one randomized trial (63 versus 70 percent at five years of follow-up) and to laparoscopic colposuspension in another randomized trial (92 versus 89 percent at four to eight years of follow-up) [43,44]. In addition, two prospective cohort studies that assessed women at 7, 11, and 17 years after retropubic MUS reported generally maintained subjective cure rates of 77 to 85 percent [45-47]. As the retropubic MUS was the first incontinence sling, most long-term data are based on this product.

Although MUS have many clinical advantages, there are few clinical contexts in which other procedures may be preferred, including women with:

●Apical pelvic organ prolapse (POP) with repair planned via laparotomy. The common teaching is that women with apical POP who require an abdominal approach for prolapse repair should have an incontinence procedure that can be performed through the same incision. For example, abdominal sacrocolpopexy for prolapse has often been performed with Burch colposuspension for incontinence. However, even in the population of women undergoing abdominal prolapse repair, many surgeons perform MUS procedures, especially when using laparoscopic or robot-assisted laparoscopic techniques. (See 'Apical prolapse' below.)

●Concomitant urethral diverticulum repair. Urethral diverticulum and management of women with recurrent SUI after surgery are discussed separately. (See "Urethral diverticulum in females" and "Stress urinary incontinence in females: Persistent/recurrent symptoms after surgical treatment".)

●Decline surgery or are not able to tolerate surgery. Women who cannot tolerate surgery and who have persistent bothersome symptoms following conservative SUI therapy should be offered treatment, including the opportunity for injection of periurethral bulking agents. (See 'Older, frail, or medically complex individuals' below.)

●Recurrent SUI. Women with recurrent SUI after initial surgical treatment who desire repeat surgery warrant a discussion of the benefits and risks around repeating the same procedure or performing a different procedure. (See "Stress urinary incontinence in females: Persistent/recurrent symptoms after surgical treatment".)

Preoperative counseling — Patient and surgeon satisfaction with treatment can be optimized by having a discussion during the planning phase for the surgery about the individual patient's goals and expectations for her treatment and awareness of potential adverse events [48,49]. Two studies have reported that increasing age, body mass index (BMI, ≥30 kg/m²), and fascial sling rather than midurethral sling were associated with decreased satisfaction following surgical treatment of SUI [50,51]. An online calculator is available to aid with decision-making in counseling patients about risk of developing SUI and urgency urinary incontinence (UUI) 12 months after sling surgery [52].

Evaluating SUI procedures — In evaluating SUI treatments, earlier investigations in pelvic reconstructive surgery focused on the objective cure rate (evaluation with office or urodynamic testing) as the primary outcome. Many experts now consider the subjective cure rate (based upon the patient's report of cure or improvement) to be the primary outcome since it is the most important to patients. In general, objective cure rates are often higher than subjective cure rates, and thus, may lead to different conclusions. In the following sections, we will report subjective rather than objective cure rates whenever possible.

COEXISTENT ANATOMIC OR FUNCTIONAL ABNORMALITY

Apical prolapse — The merit of a vaginal versus an open abdominal approach for the treatment of apical prolapse remains a topic of debate among experts. Women with apical prolapse can undergo prolapse repair by an abdominal route (abdominal sacrocolpopexy via open, laparoscopic, or robot-assisted routes) or a vaginal route (sacrospinous ligament suspension or uterosacral vaginal vault suspension). Historically, for women with both pelvic organ prolapse (POP) and stress urinary incontinence (SUI), colposuspension has been performed at the time of abdominal colpopexy, and sling procedures have been performed with vaginal POP repair. Combining abdominal sacrocolpopexy with Burch colposuspension allows for the use of a single abdominal incision, avoids additional incisions, and avoids insertion of transvaginal synthetic mesh. However, midurethral sling (MUS) procedures have higher rates of cure and symptom improvement, shorter recovery, and lower rates of some complications compared with colposuspension, which makes them the most commonly performed incontinence procedures, even in women undergoing abdominal prolapse repair [36]. Consideration of these issues, in addition to discussion of staged versus concurrent procedures for POP and SUI, is presented in detail separately. (See "Pelvic organ prolapse and stress urinary incontinence in females: Surgical treatment".)

Advanced prolapse and occult SUI — Advanced POP and SUI commonly coexist; however, in many women, the SUI may become apparent only when the prolapse has been corrected. This phenomenon is known as occult SUI and is not reliably predicted by only using preoperative urodynamic testing with prolapse reduction. Concomitant anti-incontinence surgery in women with advanced POP is discussed separately (algorithm 1). (See "Pelvic organ prolapse and stress urinary incontinence in females: Surgical treatment", section on 'Symptomatic POP without symptomatic SUI'.)

Lack of urethral hypermobility and intrinsic sphincter deficiency — There has been a debate among experts regarding whether management should differ for women with SUI and urethral hypermobility versus those who lack urethral hypermobility and may have intrinsic sphincter deficiency (ISD) [13,53]. ISD has historically been defined as a maximal urethral closure pressure <20 cm H2O and/or a Valsalva leak-point pressure <60 cm H2O. These cut-offs are highly arbitrary and have been found to have limited predictive value in determining postoperative outcomes for primary SUI treatments [54]. Studies have found that lack of urethral hypermobility and ISD are not necessarily a unified clinical entity since these issues coexist in many, but not all, women [55,56]. The current understanding is that urethral sphincter function is compromised to some degree in all women with SUI.

In our practice, we no longer routinely test for urethral hypermobility (ie, with a cotton swab test) since the results do not impact the choice of a primary anti-incontinence procedure (see "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure", section on 'Assessing urethral mobility'). Further, since ISD has been considered a urodynamic diagnosis and the clinical utility of routine urodynamic testing in women with uncomplicated SUI remains unknown, there is no rationale to support its routine assessment. (See "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure", section on 'Urodynamic testing'.)

Women without urethral hypermobility may be successfully treated with an MUS. There are few data regarding colposuspension in this population. Moreover, data are inconsistent regarding whether women with both ISD and a fixed urethra have a higher failure rate than women with ISD alone [57]. Some studies have reported that MUS are less effective in women without urethral hypermobility, but in general, observational studies have found high success rates (approximately 70 to 80 percent) [53,57-67]. This appears comparable to long-term studies of MUS, which have reported success rates of 77 to 85 percent [45,46]. As noted above, whether retropubic slings are more effective in women clinically suspected of having ISD than transobturator slings is under investigation. (See "Stress urinary incontinence in females: Persistent/recurrent symptoms after surgical treatment", section on 'Periurethral injection therapy' and "Surgical management of stress urinary incontinence in females: Choosing a type of midurethral sling", section on 'SUI background and treatment options'.)

The clinical dilemma in women with a lack of urethral hypermobility and/or suspected ISD is whether it is possible to identify which women are likely to fail treatment with a sling or colposuspension. There are no comparative studies regarding outcomes of bulking agents and other anti-incontinence procedures. The reported success rate of periurethral bulking agents varies from 48 to 75 percent, which is similar to the success rates for MUS [4,53]. However, symptomatic relief is short-lived following bulking agent injection, and injections typically need to be repeated every one to two years.

Further study is needed to address treatment of women clinically suspected of having ISD. Based on the available data, we suggest that these women be treated in the same manner as other women with SUI.

Mixed incontinence — Women with mixed incontinence (ie, symptoms of both SUI and urgency urinary incontinence [UUI]) benefit from surgical treatment of SUI [68,69] in addition to traditional UUI treatment such as pelvic floor muscle behavioral therapy [70] and anticholinergic medication [71,72]. The patient and clinician weigh the risks of the various therapies, including the time and cost of behavioral therapy, the need for long-term use and possible side effects of medication, severity of different symptom types (SUI versus UUI), and risks of surgery.

●Our approach – While all patients are offered initial behavioral and medical therapy because these interventions are low risk and may provide enough symptom relief to avoid the need for surgery, we generally take the following approach based on symptom severity:

•For individuals whose symptoms are nearly all urgency-related (ie, SUI is minor component), we treat the UUI symptoms with behavioral therapy, medication, botulinum toxin, or neuromodulation (eg, posterior tibial nerve stimulation and sacral nerve modulation). (See "Urgency urinary incontinence/overactive bladder (OAB) in females: Treatment", section on 'Initial approach to treatment'.)

•For individuals who have predominantly SUI symptoms, difficulty obtaining or adhering to behavioral or medical therapy, or symptoms refractory to nonsurgical therapy, we offer surgical treatment, typically with an MUS. The presence of mixed incontinence does not influence the choice of sling, which is discussed in detail separately. (See "Surgical management of stress urinary incontinence in females: Choosing a type of midurethral sling", section on 'Mixed urinary incontinence'.)

●Supporting data – Our rationale for offering SUI surgery to women with mixed incontinence is based upon data suggesting that overactive bladder (OAB) syndrome and SUI may not be separate, unrelated conditions [73] and surgical outcome data demonstrating improvement following MUS surgery [69,74-77].

•Efficacy of midurethral sling surgery for mixed urinary incontinence

-In the ESTEEM trial comparing MUS surgery alone or MUS surgery with behavioral and pelvic floor muscle therapy for individuals with at least three months of moderate or severe stress and urgency incontinence symptoms, both groups had large reductions in Urogenital Distress Inventory scores (-114.7 and -128.1 points, respectively) [77]. The model-estimated between-group difference (-13.4 points, 95% CI -25.9 to -1.0, p = 0.04) was statistically significant but did not meet the minimal clinically important difference threshold. Related and unrelated serious adverse events occurred in 10.2 percent of the participants (11.8 percent sling only and 8.7 percent combined). In a one-year planned follow-up, while nearly 30 percent (112 of 379) had treatment failure (subjective and/or objective), only two of these patients needed additional treatment for stress incontinence [69]. Both studies provide evidence for using MUS as primary treatment for the SUI component of mixed urinary incontinence, although it should be noted that a nonsurgical control group was not included.

-A secondary analysis of three multicenter trials of women with mixed urinary incontinence who underwent one of four anti-SUI procedures (retropubic MUS, transobturator MUS, Burch colposuspension, or autologous pubofascial sling) reported that the majority of women (50 to 70 percent) in each group had reductions in OAB symptoms, including UUI [76]. The percentage of women reporting symptom improvement was not statistically different between the two MUS groups (retropubic sling 66 percent and transobturator sling 71 percent). The Burch colposuspension group improved more than women undergoing a pubovaginal sling (68 versus 57 percent).

•Comparison with individuals with SUI only – While SUI surgery reduces mixed incontinence symptoms, it is less successful at resolving incontinence in those with mixed urinary incontinence compared with women with SUI only. In a 2011 systematic review and meta-analysis of six randomized trials and seven prospective studies that assessed the outcome of MUS surgery, women with mixed incontinence had lower cure rates compared with women with only SUI (56 versus 85 to 97 percent) [74]. Similarly, a subsequent cohort study of over 1000 women who underwent an MUS procedure reported lower incontinence cure rates for women with mixed incontinence compared with women with SUI only (64 versus 85 percent) [75].

•Addition of supportive therapies – While the addition of behavioral and pelvic floor muscle therapy to sling surgery does not appear to improve outcomes for the general population of individuals with mixed urinary incontinence, those with more severe UUI symptoms (ie, Urogenital Distress Inventory-irritative scores ≥50 percent) may have greater benefit with combined treatment [68].

●Choice of incontinence surgery – As there are fewer data on the Burch colposuspension in women with mixed incontinence and the surgery is more invasive, MUS is generally preferred for these women. However, Burch colposuspension may be indicated to treat mixed urinary incontinence in women having other abdominal procedures. In one prospective study of 40 women who underwent Burch colposuspension, women with mixed incontinence had no statistically significant difference in the overall incontinence cure rate compared with women with SUI only (87 versus 80 percent) at six months of follow-up [78]. In addition, Burch colposuspension may be associated with less UUI compared with traditional bladder neck slings. In a follow-up study of surgery for SUI-predominant mixed urinary incontinence, postoperative UUI was less likely in women undergoing Burch colposuspension than in women undergoing bladder neck sling procedures (29 versus 41 percent) six weeks from surgery [79]. Limitations of these studies include small sample sizes and short duration of follow-up.

SPECIAL POPULATIONS

Obese women — Several different stress urinary incontinence (SUI) surgeries appear to be effective in obese women, although increasing body mass index (BMI) has been associated with somewhat reduced efficacy compared with women of normal BMI [80]. The optimal procedure for obese women with SUI is not known. Studies of retropubic and transobturator midurethral sling (MUS) procedures among obese and nonobese women have been unable to demonstrate statistical differences in efficacy [81-86]. A case-control study reporting outcomes in 83 women who had retropubic midurethral sling surgery detected no statistically significant difference in 18-month continence rates between obese (BMI >40 kg/m²) and nonobese (BMI <30 kg/m²) women (87 versus 92 percent, respectively) [84]. Similarly, in a retrospective study of 281 women who underwent transobturator MUS surgery, the four-year objective cure rates were approximately 95 percent for both obese (BMI ≥30 kg/m²) and nonobese women (BMI <30 kg/m²) [85]. Trials of alternate surgical procedures have also reported treatment efficacy in obese women. In a trial of nearly 550 women randomly assigned to Burch colposuspension or rectus fascial sling for the primary treatment of stress predominant urinary incontinence, BMI was not associated with treatment failure at 24 months [87].

While incontinence surgery appears to be effective in obese women, weight loss is also associated with a significant reduction in the number of incontinence episodes and does not entail the risks of surgery [88]. However, weight management remains a challenge for clinicians and patients [89]. Clinicians may counsel obese patients about weight reduction as a therapeutic option for incontinence and refer to weight management programs as indicated, but weight loss should not restrict access to indicated surgery [90].

Older, frail, or medically complex individuals — The decision to proceed with anti-incontinence surgery is based upon the medical and functional status of the patient and the potential risks and benefits of the procedure. MUS surgery has similar benefits and complications in women over 70 years of age compared with younger women. As an example, two cohort studies totaling over 1500 women that assessed MUS outcome by age group reported no statistical difference in SUI failure rates or complication rates between older (mean age 75 [91] and 85 [92] years) and younger women (mean age 56 [91] and 58 [92] years). In both studies, the older women reported more persistent urgency urinary incontinence (UUI) symptoms compared with younger women (32 versus 23 percent, respectively). We counsel women ≥70 years who are preparing for MUS surgery that their urgency incontinence symptoms are more likely to persist postoperatively compared with younger women, but the surgical efficacy for SUI is the same.

A validated risk calculator has been developed to calculate individual predicted risks of bothersome SUI, bothersome UUI, positive stress test, and adverse events 12 months after MUS surgery [52].

Women with SUI who cannot tolerate, or decline, surgery and have failed conservative therapy are candidates for injection of periurethral bulking agents. The overall reported success rate of periurethral bulking agents is 48 to 75 percent [4,53,93]. Periurethral injection is discussed in more detail separately. (See "Stress urinary incontinence in females: Persistent/recurrent symptoms after surgical treatment", section on 'Periurethral injection therapy'.)

Assessment of surgical risk is discussed separately. (See "Overview of the principles of medical consultation and perioperative medicine".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Incontinence surgery in women" and "Society guideline links: Urinary incontinence in adults" and "Society guideline links: Gynecologic surgery".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Urinary incontinence in females (The Basics)" and "Patient education: Surgery to treat stress urinary incontinence in females (The Basics)")

●Beyond the Basics topic (see "Patient education: Urinary incontinence treatments for women (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Definition – Stress urinary incontinence (SUI) is the involuntary leakage of urine on effort or exertion, or on sneezing or coughing. (See 'Introduction' above.)

●Impact of childbearing – Surgical treatment of SUI is best avoided in women who plan future childbearing. (See 'Women finished with childbearing' above.)

●Types of SUI procedures – A vaginal or abdominal approach can be used for surgical treatment of SUI. Vaginal procedures include: midurethral sling (MUS), bladder neck sling, or injection of urethral bulking agents. Burch retropubic colposuspension is an abdominal procedure for SUI. (See 'Types of procedures' above.)

•SUI only – For most healthy females with SUI who desire surgical treatment, we recommend MUS placement rather than Burch colposuspension or traditional bladder neck sling (Grade 1B). This recommendation is based upon the comparable-to-superior efficacy compared with other procedures, shorter operative duration and recovery times, and lower rates of repeat incontinence surgery. Procedures that are clearly less effective than MUS are anterior colporrhaphy (even with Kelly-Kennedy plication), transabdominal paravaginal repair, and transvaginal needle suspension. Comparison of MUS types is discussed in detail separately. (See 'Comparison of efficacy' above and 'Procedures no longer recommended' above and "Surgical management of stress urinary incontinence in females: Choosing a type of midurethral sling".)

•Mixed urinary incontinence – For individuals with mixed urinary incontinence, MUS surgery is associated with a reduction in incontinence symptoms. Addition of behavioral and pelvic floor muscle therapy may provide a small increase in benefit. (See 'Mixed incontinence' above.)

●Alternative treatment option – For patients who decline or are not candidates for surgery, but have failed conservative therapy, we suggest injection of periurethral bulking agents (Grade 2C). (See 'Older, frail, or medically complex individuals' above.)