Surgical management of stress urinary incontinence in females: Pubovaginal sling procedures

INTRODUCTION — Surgical therapy for female stress urinary incontinence (SUI) includes pubovaginal slings, midurethral slings (with synthetic, polypropylene mesh), and Burch urethropexy (table 1).

Although the midurethral sling using synthetic mesh is the most common procedure for treatment of SUI and the standard of care for most patients, some patients may not be candidates or may request surgical techniques that do not use synthetic mesh [1,2]. This topic reviews pubovaginal (also known as suburethral or bladder neck) fascial sling procedures. In females undergoing surgical treatment, midurethral synthetic slings are generally preferred to pubovaginal fascial slings or Burch urethropexy [3]. However, in those who decline or are not candidates for midurethral slings, pubovaginal autologous fascial slings remain an effective treatment for SUI.

The evaluation, treatment and other surgical options for females with SUI are discussed elsewhere. (See "Female urinary incontinence: Treatment" and "Female stress urinary incontinence: Choosing a primary surgical procedure".)

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 encourage the reader to consider the specific counseling and treatment needs of transgender and gender diverse individuals.

ANATOMIC LOCATION AND MATERIALS — Pubovaginal slings are placed at the level of the proximal urethra or bladder neck [4]. The anterior rectus fascia (ie, pubovaginal sling) and pubic bone are the most common superior attachments for pubovaginal slings; however, the superior rectus fascia is preferred as most high-quality outcome data use the rectus fascia. In addition, bone anchors, used to attach the sling to the pubic bone, are associated with osteitis pubis and osteomyelitis [5] and offer no improvement in outcomes.

Sling materials include autografts (rectus fascia or fascia lata), allografts (fascia lata), xenografts (porcine dermis), and synthetic meshes (mersilene or expanded polytetrafluoroethylene). We use rectus fascia harvested from the patient (autologous) at the time of the sling surgery in most cases.

MECHANISM OF ACTION — The exact mechanism of continence created by the pubovaginal sling is unclear. It likely provides direct compression to the proximal urethra or provides a hammock against which the urethra is compressed during increases in abdominal pressure [6].

PATIENT SELECTION — Pubovaginal slings are reserved for women in whom midurethral slings are contraindicated, were unsuccessful, or who decline to have a synthetic material used for their sling. Two studies reported high SUI cure rates (70 to 90 percent) after pubovaginal sling procedures in women with prior unsuccessful synthetic midurethral sling insertions, particularly for women whose synthetic mesh was removed [7,8]. However, in general, the midurethral sling is the standard of care for SUI, largely due to the decreases in morbidity and voiding dysfunction associated with midurethral slings as compared with pubovaginal slings [9]. (See "Female stress urinary incontinence: Choosing a primary surgical procedure" and "Female stress urinary incontinence: Choosing a primary surgical procedure", section on 'Types of procedures'.)

PREOPERATIVE EVALUATION AND CONSIDERATIONS — All women undergoing pubovaginal slings should at a minimum:

●Report bothersome SUI symptoms

●Demonstrate signs of SUI (ie, transurethral urine loss with increase in intraabdominal pressure prior to surgery)

Office evaluation is adequate for women with predominant SUI symptoms planning to undergo a pubovaginal sling [10,11]. If the urinalysis, cough stress test, and postvoid residual urine volume are consistent with uncomplicated SUI, then urodynamic testing is unnecessary. The additional information provided from urodynamic testing may be warranted in women who have persistent SUI symptoms after prior incontinence surgery, who have complicated urinary tract histories, who have urethral incompetence, or who have symptoms of mixed urinary incontinence. The preoperative evaluation of women undergoing incontinence surgery is discussed in more detail elsewhere. (See "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure" and "Surgical management of stress urinary incontinence in females: Preoperative evaluation for a primary procedure", section on 'Office testing'.)

Consent — Women are counseled regarding the alternative nonsurgical and surgical therapies as well as risks, benefits, complications, and success rates of pubovaginal slings. (See "Informed procedural consent", section on 'Informed decision-making'.)

Antibiotic prophylaxis — We agree with the American College of Obstetricians and Gynecologists and the American Urological Association recommendation for antibiotic prophylaxis (table 2). (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults", section on 'Antimicrobial prophylaxis'.)

Venous thromboembolism prophylaxis — We recommend sequential compression devices as a minimum intervention and consider additional pharmacologic prophylaxis in patients with multiple risk factors (see "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients"). Rectus fascial sling is typically classified as a "high-risk" procedure for developing venous thromboembolism (VTE) [12]. A retrospective analysis of VTE in women undergoing urogynecologic surgery who were treated with sequential compression devices reported a VTE incidence of 0.3 percent [13].

TECHNIQUE — Autologous pubovaginal slings are constructed from abdominal rectus fascia or fascia lata. Rectus fascia was used in the earliest reported slings as it was in the operative field, and it continues to be the best studied sling graft material. Fascia lata is a reasonable alternative if the rectus fascia is insufficient or there is a large pannus. Rectus fascia and fascia lata share the benefits of being autologous materials with low rates of graft-related complications and failures when compared with allografts, xenografts, and synthetic meshes [14,15].

The harvested fascia is placed transvaginally at the level of the proximal urethra, adjacent to the bladder neck. Permanent sutures are attached to the corners of the sling, passed retropubically, then secured superiorly above the rectus fascia [16,17]. The technique varies somewhat based on the sling material (autologous fascia, allograft, xenograft, or synthetic); however, the most high-quality outcome data exist using rectus fascia as the sling material [16]. Our technique for autologous rectus fascial sling is described in more detail below:

●Anesthesia – Rectus fascial sling procedures are performed in the operating room under regional or general anesthesia.

●Positioning – The patient is positioned in dorsal lithotomy position to allow for combined access to the lower abdomen and vagina. A bladder catheter is inserted and kept for the remainder of the case.

●Harvesting fascia and preparing sling – A small 4 to 5 cm transverse suprapubic incision is made and a rectangular piece of rectus fascia (approximately 2 x 8 cm) harvested. The harvest site is closed in a tension-free fashion using a delayed absorbable suture. Permanent sutures are affixed to the four corners of the harvested rectus fascia.

●Vaginal dissection – A midline incision is made in the anterior vaginal wall at the level of the urethrovesical junction. The urethrovesical junction is easily identified by applying gentle downward traction on the bladder catheter so the balloon resides at the bladder neck, and thus identifies the urethrovesical junction. Using a combination of blunt and sharp dissection, the surgeon creates peri-urethral and retropubic tunnels bilaterally; the tunnels start in the vaginal dissection and extend into the retropubic space. Once the surgeon can feel the bottom of the pubic symphysis in the peri-urethral tunnel, she advances her finger into the retropubic space (aiming towards the ipsilateral shoulder), while gently swiping the bladder medially to prevent perforation.

●Passing sling – A long instrument (eg, uterine packing forceps or Stamey needle) is passed through the rectus fascia, behind the pubic bone, into the retropubic space and exits through the vaginal incision described in the paragraph above. The sling suture arms are grasped with the clamp and then passed from the vaginal to the abdominal fields. This is repeated on both sides, so that the sling lay under the urethrovesical junction or proximal urethra. Several fine absorbable sutures are placed to fix the sling to the periurethral tissues. Although surgeons have used bone anchors in the pubic symphysis as the superior sling attachment site, rectus fascia is preferred because bone anchors are associated with complications such as osteomyelitis pubis and do not improve the continence outcome.

●Cystoscopy – Cystoscopy is performed with a 70-degree cystoscope to ensure the sling and dissection have not perforated the bladder and both ureters efflux briskly. The urothelium should also be assessed for any abnormalities.

●Tensioning sling – The sling suture arms are then pulled up and tied above the rectus fascia, so the sling lays at the proximal urethra under no tension. A small curved clamp can be placed between the sling and the urethra; the clamp prevents overtightening the sling.

●Incision closure – The vaginal skin incisions using a running fine absorbable suture; the skin incision is closed in a subcuticular fashion.

OTHER SLING MATERIALS

Autologous slings — Fascia lata and rectus fascia share the benefits of being autologous materials with low rates of graft-related complications and/or failures when compared with allografts, xenografts, and synthetic meshes [14,18]. While no comparative data exist, most surgeons prefer rectus fascia to fascia lata because it is done through the same suprapubic incision that is used to secure the sling arms to the rectus fascia. Fascia lata harvesting requires patient repositioning during the surgery to allow access to the leg, and a leg incision. However, fascia lata is an alternative for patients with contraindications to harvesting rectus fascia (eg, prior low ventral hernia repair with mesh).

Allograft slings — Allograft slings (cadaveric fascia lata or lyophilized dura mater) have been used to decrease the morbidity associated with harvesting autologous grafts (see "Reconstructive materials used in surgery: Classification and host response", section on 'Allografts'). However, allograft pubovaginal slings are less effective when compared with autologous pubovaginal slings. In a 2011 meta-analysis of six trials, patient-reported improvement rates within one year of surgery favored autologous rectus fascia over other biological materials [15]. In general, allografts are reserved for patients who are not candidates for mesh and who decline the use of autografts.

Xenograft slings — Xenograft pubovaginal slings are generally not used secondary to high SUI recurrence rates [19,20]. The rationale for xenograft use was to minimize morbidity associated with harvesting allografts and complications associated with mesh. (See "Reconstructive materials used in surgery: Classification and host response", section on 'Xenografts'.)

One multicenter trial randomized 201 women with urodynamically proven stress incontinence to receive either a porcine dermis xenograft pubovaginal sling, autologous fascial pubovaginal sling, or polypropylene mesh midurethral sling [20]. At six months postoperatively, SUI improvement rates in the porcine dermis arm were significantly lower than autologous fascial and mesh slings (73 versus 95 versus 92 percent, respectively). Similarly, a case series using porcine dermis pubovaginal slings reported SUI success rates of 43 percent, with a mean time to recurrence of 10.4 months [19].

Synthetic slings — Pubovaginal and midurethral slings are synthetic type I meshes constructed of polypropylene (see "Reconstructive materials used in surgery: Classification and host response", section on 'Synthetic materials'). The majority of incontinence slings are midurethral polypropylene slings. The use of other synthetic material for pubovaginal slings (polyethylene and expanded polytetrafluoroethylene) has been associated with urethral erosion rates of 8 and 12.5 percent, respectively [21,22].

COMPLICATIONS — Minor complications or adverse events after autologous fascia pubovaginal sling can range from 29 to 63 percent [16,23], while serious adverse events in one randomized trial occurred in only 13 percent [16]. Some of the more common complications are highlighted below:

●Cystitis – Cystitis is the most common immediate adverse event after pubovaginal sling, with 48 percent of patients having a urinary tract infection during two years of follow-up [16]. As positive urine cultures were not required in this study, the reported rate of urinary tract infection may be overestimated.

●Urinary retention – One trial of 655 women randomized to pubovaginal sling or Burch procedure reported greater urinary retention rates for the pubovaginal sling patients than the Burch patients (66 percent versus 42 percent) [16].

●Urge urinary incontinence – Rates of postoperative urinary urge incontinence range from 18 to 40 percent [16,23,24]. In one study, women who had a pubovaginal sling compared with women who had Burch procedure were almost twice as likely to receive treatment for postoperative urge urinary incontinence six weeks after surgery [24].

●Voiding dysfunction – Voiding dysfunction after pubovaginal sling ranges from 10 to 14 percent in the first six to eight weeks after surgery [16,23].

●Cystotomy – Incidence of cystotomy at the time of rectus fascial sling ranges from 1 to 3 percent [16,19]. Reported incidence of bladder perforation is lower with rectus fascial sling compared with retropubic midurethral sling [25], possibly because of the more extensive dissection with suburethral rectus fascial sling.

POSTOPERATIVE CARE — Because of the risk of prolonged urinary retention and voiding dysfunction postoperatively, all women undergo a standardized voiding trial prior to discharge or removal of an indwelling catheter [26]. A commonly used protocol includes retrograde filling the bladder with 300 mL of sterile saline or water through the patient’s catheter. The catheter should be immediately removed and the patient asked to void on the toilet with a collection device to measure the voided volume. If the patient voids at least 150 mL, the catheter does not need to be replaced. Women with elevated postvoid residual urine volumes (>150 mL) should have some type of ongoing bladder drainage (intermittent self-catheterization, indwelling transurethral catheter, or suprapubic catheter) until urinary retention resolves (see "Acute urinary retention", section on 'Bladder decompression'). In women undergoing midurethral sling, no patient who met these criteria required additional catheterization [27]; however, given the higher retention rates after pubovaginal slings, the false positive rate may be higher. Occasionally, if urinary retention persists, additional surgery may be necessary to loosen the sling. The timing for facial sling release varies by surgeon and ratio of voided to postvoid residual urine volumes over time. If the patient requires catheterization beyond four to six weeks, we recommend loosening of the sling to minimize risks of developing urinary urgency and urgency incontinence. Pelvic floor physical therapy with mobilization of the vaginal and abdominal incisions can hasten resumption of normal voiding in some women.

Incisional pain is typically well controlled with oral anti-inflammatory agents and narcotics. Patients can expect pain resolution in the first few weeks after surgery. (See "Approach to the management of acute pain in adults".)

Patients are counseled to expect some vaginal spotting from the vaginal incision and refrain from placing anything in the vagina or having vaginal intercourse for four to six weeks while the incision heals. Few data exist to guide surgeons and patients regarding resumption of normal activities. Patient information regarding care after pelvic surgery can be found separately. (See "Patient education: Care after gynecologic surgery (Beyond the Basics)".)

CONTINENCE RATE — Efficacy of pubovaginal slings varies by comparator [3,16,28].

●In a 2007 randomized trial comparing autologous fascial pubovaginal sling with Burch colposuspension, the overall continence rates were statistically higher with fascial sling (47 versus 38 percent) at 24-month follow-up [16]. Similarly, treatment satisfaction rates at 24 months were statistically higher in the pubovaginal sling patients as compared with the Burch procedure patients (86 versus 76 percent).

●In a 2014 meta-analysis of randomized trials, autologous fascial pubovaginal sling (pubovaginal type) compared with midurethral sling, subjective cure favored midurethral sling (odds ratio [OR] 0.40, 95% CI 0.18-0.85) [3].

●In a 2020 meta-analysis that included 14 trials comparing continence outcomes for pubovaginal slings and midurethral slings, pubovaginal slings were probably not better and possibly less effective in the first one to five years after surgery (67 versus 74 percent, OR 0.67, 95% CI 0.44-1.02, n = 458). However, midurethral slings were associated with fewer perioperative complications (risk ratio 1.74, 95% CI 1.16-2.60) [28].

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".)

SUMMARY AND RECOMMENDATIONS

●Patient selection – Pubovaginal slings are reserved for rare individuals in whom midurethral slings are contraindicated, were unsuccessful, or for those who decline a synthetic sling. Midurethral slings are preferred because of similar efficacy with decreased morbidity, urinary tract infection, and voiding dysfunction. (See 'Patient selection' above.)

●Indications – Women undergoing pubovaginal slings should, at a minimum, report bothersome SUI symptoms, demonstrate signs of SUI, and have a normal postvoid residual urine volume and a negative urinalysis. (See 'Preoperative evaluation and considerations' above.)

●Evaluation – Office evaluation is adequate for women with predominant SUI symptoms planning to undergo a pubovaginal sling. If the urinalysis, cough stress test, and postvoid residual urine volume are consistent with uncomplicated SUI, then urodynamic testing is not necessary. (See 'Preoperative evaluation and considerations' above.)

●Surgical materials

•Autologous fascia– Rectus fascia harvested from the patient (autologous graft) is the preferred non-mesh graft material because it has the highest success rate for treating SUI and minimizes the number of surgical sites. (See 'Technique' above.)

•Allografts – Allografts are reserved for patients who are not candidates for mesh or autologous graft, but the continence failure rates are higher than for mesh and autologous graft. We do not use xenografts because of the high rate of SUI recurrence. (See 'Other sling materials' above.)

●Surgical procedure – Pubovaginal fascial slings are placed at the level of the proximal urethra or bladder neck. The superior attachment of the sling arms is to the rectus fascia. We do not use bone anchors because of higher risk of failure and complication. (See 'Technique' above.)

●Complications – Common complications of pubovaginal slings include cystitis, urinary retention, and voiding dysfunction. (See 'Complications' above.)

●Postoperative voiding trial – All women should undergo a standardized voiding trial after placement of a pubovaginal sling. A common protocol includes retrograde filling the bladder with 300 mL of sterile saline or water through the patient’s catheter. The catheter should be immediately removed and the patient asked to void on the toilet with a collection device to measure the voided volume. If the patient voids at least 150 mL, the catheter does not need to be replaced. Women with elevated postvoid residual urine volumes (>150 mL) should have some type of ongoing bladder drainage (intermittent self-catheterization, indwelling transurethral catheter, or suprapubic catheter) until urinary retention resolves. (See 'Postoperative care' above.)

●Continence rates – Continence rates after pubovaginal slings vary by comparator but are generally acceptable with high patient satisfaction rates. (See 'Continence rate' above.)