Stress Urinary Incontinence

Etiology

Stress urinary incontinence occurs when the pressure inside the bladder exceeds the urethra's ability to remain closed, often due to damage to the sphincteric muscles that maintain continence. The etiologies of stress urinary incontinence are multifactorial and include the following: [5][6]

• Loss of support from pelvic floor musculature and connective tissue and urethral hypermobility: This involves the loss of pelvic support, which can originate from connective tissue disorders; chronic cough; obesity; pelvic floor trauma; vaginal delivery, especially if traumatic; pregnancy; pelvic or vaginal surgery; genitourinary syndrome of menopause or other hypoestrogenic states; chronic constipation; heavy lifting; and smoking. This is the most common etiology of stress incontinence in women.

• Intrinsic sphincter deficiency: This is due to sphincteric neuromuscular dysfunction or damage from previous pelvic surgeries, neuropathic and spinal disorders, trauma, cauda equina, sacral and severe pelvic fractures, nerve injury from abdominal surgeries, myelodysplasia, radiation therapy of the pelvis, or complications of urological surgery such as transurethral resection of the prostate or radical prostatectomy. The degree of leakage tends to be greater and may result in continuous dripping. Intrinsic sphincter deficiency may occur in both genders but is the most common etiology of significant stress incontinence and continuous urinary leakage in men. 

• Although vaginal atrophy is most common in menopausal patients, it can affect women of any age who experience decreased estrogen stimulation of the urogenital tissues. In premenopausal women, a hypoestrogenic state may occur during the postpartum period, with lactation, or due to conditions such as hypothalamic amenorrhea or the use of antiestrogenic drugs. Importantly, not all patients with atrophic vulvovaginal changes observed during a pelvic examination exhibit symptoms. Please see StatPearls' companion resource, "Vaginal Atrophy," for more information.

Recent research indicates that heavy metal exposure, particularly in younger and middle-aged females, is positively associated with stress incontinence. Elevated levels of lead and cadmium in the serum and cadmium and cesium in the urine are positively associated with the risk of stress incontinence.[7] In a retrospective study involving 590 women, high-density lipoprotein (HDL) cholesterol levels were negatively correlated with the development of stress urinary incontinence.[8] Specifically, higher levels of HDL were associated with a lower risk of stress incontinence. Targeting HDL levels offers a potential future avenue for preventing and treating stress urinary incontinence.[8]

Epidemiology

Overall, it has been estimated that almost 62% of women experience some degree of urinary incontinence.[9] Of these, 37.5% have stress urinary incontinence, and another 31% report the mixed type.[9] Stress urinary incontinence is the most common type of urinary leakage disorder in women, and the prevalence is increasing.[10][11] This condition is prevalent in older females living in nursing homes, with up to 77% affected.[10][12] 

Among women with stress urinary incontinence, 77% find their leakage problem bothersome, 28.8% report symptoms as moderate to severe, and 22% describe their urinary leakage as severe.[9][13] 

In Europe, the prevalence of stress urinary incontinence was estimated at 14.5% in 2022 among individuals aged 30 to 60. In Romania, the prevalence is estimated at 18% or higher, reflecting underreporting issues.[14][15] The occurrence of stress urinary incontinence among adult women in China has been reported at 18.9%.[16]

The prevalence of stress urinary incontinence in women increases with age (>70 years), menopause, obesity (body mass index at least 25 and especially >40), and the number of vaginal births.[9] 

In addition to body mass index, various obesity measurements, such as the weight-adjusted waist index, have been associated with female urinary incontinence in the United States.[17][18][19] A visceral adipose index has been used as a parameter for visceral obesity and is significantly correlated with stress urinary incontinence.[20][21] 

Other identified risk factors include anxiety, depression, functional dependence, and non-Hispanic White ethnicity.[9]

Stress incontinence during pregnancy significantly increases the risk of having stress urinary incontinence 12 years after childbirth.[17] 

Despite its high prevalence and impact, only 60% of women with incontinence symptoms seek treatment.[22] 

In men, urge incontinence, typically related to benign prostatic hyperplasia, is far more common (80%) compared to stress incontinence (10%), which is generally a postoperative issue. The rate of significant, bothersome, chronic, ongoing stress incontinence after radical prostate surgery is about 5% to 10%.[23][24][25][26][27]

Urinary incontinence symptoms are also more likely to be overlooked in men due to embarrassment and the perception that urinary leakage is a woman's problem.[28][29]

Pathophysiology

Current understanding mainly attributes stress urinary continence in women to the coordinated contraction of the levator ani muscle and the external urethral sphincter. The contraction results in the urethral bend angle and the closure of the urethra. Other essential factors contribute to the maintenance of continence, including the anatomical features of the periurethral tissues, the urethra, and the pelvic floor nerves.[2] Therefore, the pathophysiology of stress urinary incontinence is multifactorial.

Risk factors, such as age, childbirth, menopause, obesity, multiple vaginal births, and others, induce alterations in the anatomical components responsible for continence.[2]

Pelvic floor muscle weakness is a critical factor, often resulting from childbirth, increased abdominal pressure, pelvic surgery, connective tissue disorders, or neurological conditions. Please see StatPearls' companion resource, "Pelvic Floor Dysfunction," for more information.

In addition, the pathophysiology of stress urinary incontinence can involve distortions in the normal anatomical relationship between the urethra and bladder. These distortions, which may occur due to increased intra-abdominal pressure, lead to intravesical pressure exceeding urethral pressure, resulting in urine leakage. Examples include funneling and descent of the vesical neck, abnormal downward and backward rotation of the urethral axis, and loss of the posterior urethrovesical angle. Alterations in the circular muscular arrangement can also reduce urethral resting tone and closing pressure, further contributing to incontinence.

In men, prostatic surgery is primarily responsible for most cases of male stress urinary incontinence. Surgical removal of the prostate often necessitates damage to or removal of the internal urinary sphincter. There may also be direct or indirect damage to the external urinary sphincter and its surrounding tissues during prostate surgery.

History and Physical

Obtaining a detailed patient history and performing a thorough physical examination are crucial for diagnosing stress urinary incontinence. Specific information about the circumstances under which the patient experiences urine leakage should be gathered, noting whether the incontinence occurs exclusively during activities that increase intra-abdominal pressure, such as coughing, sneezing, laughing, or physical exertion. The severity of the condition should be assessed by evaluating its frequency, progression, and impact on the patient's social interactions and quality of life. This comprehensive assessment helps determine the necessity for more aggressive evaluation and intervention.

The patient's history should include a detailed characterization of the following:

• Fluid intake patterns
• medical and surgical history with particular attention to any history of urinary tract infections, diabetes, urologic surgery, obstetric trauma, pelvic radiation, and central nervous system or spinal cord disorders
• Medications
• Menopausal status or the presence of hypoestrogenism
• Nocturia
• Psychological stress
• Stressors or precipitating events causing a loss of urine
• Temporal relationship between the stressors and the loss of urine
• Types of protective products used, such as tampons, pads, or diapers, and the number used daily
• Voiding pattern

A voiding diary should document the number of accidents with the time of day, amount of fluid intake, amount voided versus leakage, and association of activity.[1][30][31][32] A 3-day voiding diary is optimal, a 2-day diary is acceptable, and even a single 24-hour voiding diary can be helpful as patient compliance with preparing and recording longer voiding diaries is problematic. Studies have demonstrated the positive utility of targeted patient questionnaires in identifying important stress incontinence-related domains.[33]

The physical examination is crucial for ruling out other causes of incontinence and providing a comprehensive assessment of the patient's condition. The examiner should note if the patient has a large panniculus, surgical incisions, or adequate suprapubic muscle tone. In addition, the examination may identify exacerbating conditions such as chronic obstructive pulmonary disease, obesity, or intra-abdominal masses, which can influence the severity and management of incontinence. A thorough neurological examination is also essential.

The pelvic examination should be conducted with the patient both standing and supine and with a full and empty bladder. Evidence of pelvic relaxation, such as cystocele, rectocele, or uterine prolapse, may be observed during the pelvic examination. A pelvic mass may also be detected. For postmenopausal women, assessing the estrogen status of the vagina and bladder is essential, as estrogen deficiency significantly contributes to incontinence. A positive cough stress test can be used to demonstrate stress incontinence subjectively.

The degree of uterine and bladder prolapse should be assessed using a pelvic organ prolapse quantification system.[1] The presence of pelvic organ prolapse beyond the hymen (fourth degree) is consistent with complicated clinical situations and can mask or reduce the apparent severity of the patient's stress incontinence.[34] In cases of advanced-stage cystoceles, stress incontinence is observed in a ratio of 3:1:1 among cases with overt, occult, and no demonstrable symptoms, respectively.[35]

Evaluation

Initial evaluation of any form of incontinence should encompass the following: [1]

• A 24-hour voiding diary (a 3-day diary is preferred, but patient compliance is easier to achieve with a 1-day diary).
• Detailed history, particularly the genitourinary review of systems, prior surgeries, childbirth, and voiding history.
• Physical examination with the demonstration of stress urinary incontinence in both supine and upright positions.
• In females, a careful and complete pelvic examination with an assessment of urethral hypermobility (Q-tip test).
• Measurement of the postvoid residual urine volume.
• Urinalysis with or without a urine culture to diagnose urinary tract infection or underlying renal disease such as stones or tumors.
• Urodynamic testing is not indicated in the initial evaluation of uncomplicated stress urinary incontinence.

Indications to consider urodynamics testing or video urodynamics studies include patients with complicated incontinence symptoms, significant comorbidities, individuals older than 60, continuous or unpredictable leakage, failed prior surgical incontinence treatment, after pelvic radiation therapy, diagnostic uncertainty, or a history of radical pelvic surgery. Such urodynamics testing should include leak point pressure and maximum urethral closure pressure measurements. Please see StatPearls' companion resource, Urodynamic Testing and Interpretation, for more information.

Evidence suggests that urodynamic testing and imaging are unnecessary before surgical management in uncomplicated cases, as they are unlikely to impact treatment outcomes.[1] However, urodynamic testing or videourodynamic studies can be valuable in complex presentations or selected cases of mixed incontinence and are often performed preoperatively.[1][36]

Blood work may be indicated to rule out diabetes or other systemic disorders. Cystoscopy may occasionally be performed to rule out intrinsic lesions of the bladder mucosa and urethra and to evaluate the internal sphincter and bladder neck.

The Q-tip test, first described in 1971, is frequently performed as an office test to assess female urethral hypermobility, which is defined as a 30° or greater angle displacement from the resting position (baseline) while bearing down (Valsalva) with the patient in the supine position.[1][37][38][39]

The test is performed by placing a lubricated sterile cotton swab (Q-tip) into the urethra so the tip sits at the bladder neck. With the patient in the supine position, the angle between the baseline (resting) and the active or straining (Valsalva) positions is measured with a 30° or greater angle, indicating a positive result.[37][38] This test can be challenging for inexperienced clinicians, as the duration of the active deflection may be very brief, making it difficult to measure or record. In addition, the procedure may be embarrassing and uncomfortable for the patient, and sometimes, the Q-tip may stiffen the urethra, leading to a false negative result.[37][38] There is also a small chance of inducing a urinary tract infection.[38]

The Q-tip test is a simple, clinically useful diagnostic tool that can be quickly performed in the office setting to identify pelvic relaxation, possibly associated with stress urinary incontinence.[37][38] A positive test in a patient with symptoms of stress incontinence is highly suggestive of the diagnosis and associated with a higher success rate from incontinence surgery.[37][38][40] However, a negative test should be a cause for concern, as it indicates that the patient's leakage may be due to factors other than urethral hypermobility and pelvic relaxation.[37][38]

Transperineal ultrasound could be an alternative noninvasive method to the Q-tip test for assessing urethral hypermobility in patients with stress urinary incontinence.[37] The bladder neck rest-stress distance on ultrasound with a cut-off value of 13.3 mm correlated well with the Q-tip test angle results with good specificity and positive predictive values for diagnosing urethral hypermobility in women with urinary stress incontinence.[37]

Urodynamics 

Maximum urethral closure pressure: This is the maximum difference in pressure between the urethra and bladder.[41] A normal maximum urethral closure pressure is generally considered more than 30 cm H₂O, whereas values less than 20 cm H₂O indicate intrinsic sphincter deficiency or urethral dysfunction.[41][42] Results between 20 and 30 cm H₂O pressure are considered equivocal.[41][42] The maximum urethral closure pressure is 40% less in women with stress incontinence than that of normal continent controls.[41][42] A similar measurement during stress (coughing or Valsalva) is also useful but harder to reproduce due to the variable intensity of the patient's Valsalva and movement of the urethral pressure catheter.[43]

Valsalva leak point pressure: This is the minimum intravesical pressure required to demonstrate urinary leakage during stress (Valsalva) without a detrusor contraction.[44] This measurement helps differentiate intrinsic sphincter deficiency from bladder neck and urethral hypermobility.[44] If leakage is noted at a bladder pressure of 60 cm H₂O or less, it suggests intrinsic sphincter deficiency. Values greater than 90 cm H₂O indicate normal sphincteric competence, whereas results between 60 and 90 cm H₂O are considered equivocal.[44] The Valsalva leak point pressure is relatively easily measured and more reproducible compared to other forms of leak point pressure testing, making it the preferred method.[44][45]

Intrinsic sphincter deficiency: This deficiency is diagnosed through clinical history and the following criteria:

• A negative Q-tip test (<30°).
• Transperineal ultrasound showing a bladder neck rest-stress distance of less than 13.3 mm.
• Maximum urethral closure pressure less than 20 cm H₂O.
• Valsalva leak point pressure of less than 60 cm H₂O.
• Fixed, lead pipe, or stove pipe urethral imaging on videourodynamics or voiding cystourethrogram.
• Funneling of the bladder neck on voiding cystourethrography, possibly showing a breaking appearance.
• Bladder neck mobility of less than 20° with Valsalva.
• An open proximal urethra at rest.
• No closure of the proximal urethra, indicating loss of internal sphincter activity.
• An open bladder neck on cystoscopy, ultrasound, MRI, or other imaging study.

Less experienced clinicians may refer the patient to a urogynecologist or urologist for medical or surgical treatment, opting to co-manage the condition. A referral to a urogynecologist or urologist should be considered for patients with the following:

• Abnormal pelvic anatomy
• Coexisting neurological conditions
• Diagnostic uncertainty
• Equivocal urodynamic testing
• Failed medical therapy
• Pelvic radiation therapy
• Prior incontinence or significant pelvic surgery
• Prolapse
• Recurrent urinary tract infections
• Significant bladder overactivity
• Unexplained hematuria
• Unusually severe incontinence

Treatment / Management

The treatment of stress urinary incontinence is subdivided into behavioral, mechanical, pharmacological, and surgical management. Regardless of whether the patient desires any of the 4 options, all patients should receive counseling on lifestyle modifications, including weight loss, smoking cessation, managing constipation, and avoiding food and beverages known to exacerbate bladder conditions. Common bladder irritants include caffeinated beverages such as coffee, tea, and sodas; alcohol; citrus fruits; chocolate; tomato; spicy foods; and tobacco.[46][47]

Behavioral Methods

Bladder retraining (timed voiding): This method involves regularly scheduling urination to keep the bladder empty for longer periods throughout the day. In a study, 32 females with incontinence who were treated with a bladder retraining program alone experienced a 72% improvement rate assessed by cystometrogram.[48]

Pelvic muscle and pelvic floor muscle training exercises: These exercises are widely recommended, with Kegel exercises being the most common. These exercises consist of 3 sets of 10 pelvic musculature contractions, each held for 10 seconds at least 3 times daily. However, a primary issue hindering the continuity of pelvic floor muscle training exercises is the lack of patient motivation and inconsistency in execution.[49] A systematic review of 23 clinical trials found that pelvic floor muscle training can significantly reduce stress urinary incontinence, and its effectiveness can be further improved when combined with bladder training.[50] (A1)

Targeting core musculature is increasingly believed to be essential in pelvic floor rehabilitation. A single-blinded, randomized trial involving 90 females aged 18 to 40 compared Kegel exercises to dynamic neuromuscular stabilization. The results showed dynamic neuromuscular stabilization was superior to Kegel exercises for stress urinary incontinence treatment.[51]

Biofeedback: Visual or audio signals can provide feedback on the correct contraction of pelvic floor muscles. A review of 21 studies indicated that pelvic floor muscle training combined with electromyographic biofeedback achieves better outcomes compared to pelvic floor muscle training alone in treating patients with stress urinary incontinence.[52] Please see StatPearls' companion resource, "Biofeedback," for more information.(A1)

Electrostimulation: This technique uses electrical stimulation through acupuncture needles for 30 minutes weekly for 12 weeks, followed by monthly maintenance sessions. Electrostimulation aims to stimulate the pudendal nerve and induce contractions of the pelvic floor muscles, thereby enhancing the urethral sphincter's intrinsic closing mechanism.[53]

Insertable Mechanical Devices

Pessaries: These devices should be considered for all women presenting with stress urinary incontinence, especially when conservative management is appropriate. Ideal candidates for pessary use include pregnant women, older women for whom surgery poses a risk, and those who have had unsuccessful previous surgeries for stress urinary incontinence. In addition, pessaries are a viable option for patients who experience stress urinary incontinence only during strenuous physical activity.[54] Contraindications to pessary placement include an active pelvic or vaginal infection, severe ulceration, allergies to silicone or rubber, and noncompliance or difficulty with follow-up.[55] (B2)

Pessaries aid in supporting the urethra and bladder wall, elongating and elevating the urethrovesical angle, and gently compressing the urethra against the pubic bone.[55] The incontinence ring with and without support and incontinence dish pessaries are specifically designed to manage stress urinary incontinence. The most commonly used pessaries for stress urinary incontinence are the ring and Gellhorn pessaries.(B2)

Proper fitting of the pessary is critical. The patient should be fitted with the largest pessary that fits comfortably and examined in both supine and standing positions.[56] The pessary must remain comfortably in place during a Valsalva maneuver and voiding. Proper sizing and fitting are confirmed when the clinician can place a finger between the pessary and the vaginal wall.[57] If the pessary is too tight, it may cause urinary obstruction with subsequent urinary retention, and if the pessary is too small, it typically falls out soon after placement. 

Bladder vaginal supports: These devices are collapsible silicone devices encased in a non-absorbent polypropylene covering. When inserted into the vagina, the support expands to elevate and stabilize the urethra, effectively preventing leaks caused by activities such as coughing, sneezing, or exercising. These devices are typically used for up to 8 hours in a 24-hour period. Similar to tampons, they have a minimal risk of toxic shock syndrome.

Pharmacologic Options

Anticholinergics: Medications, such as oxybutynin, block muscarinic receptors in the smooth muscle of the bladder, inhibiting detrusor contractions. Similar bladder-relaxing effects can be obtained from beta-3 adrenergic agonists, such as mirabegron and vibegron, without the anticholinergic adverse effects.[58] Although these medications help relax the bladder, they do not directly affect sphincteric competence but can be useful in mixed incontinence cases. Please see StatPearls' companion resources, "Anticholinergic Medications" and "Mirabegron," for more information.

Duloxetine: This medication is associated with the reuptake inhibition of serotonin and norepinephrine at the pudendal nerve.[59] Duloxetine can increase the activity of the external urethral sphincter and can significantly reduce stress incontinence episodes in up to 64% of patients.[60][61] However, it is not currently FDA-approved in the United States or Japan for the treatment of stress urinary incontinence.[60]

Vertigo and gastrointestinal upset (nausea) are common adverse effects of duloxetine, and an increased risk of suicide and violence in patients with concomitant major depression has been noted.[62][63][64][65] Vertigo is a common cause of drug discontinuation by patients.[60] Although reducing the dose to 20 mg BID decreases nausea and patient discontinuation rates, the overall risk-benefit ratio for duloxetine in treating stress urinary incontinence remains unfavorable outside of Europe, where it is approved for moderate to severe cases.[62][63][66] Please see StatPearls' companion resource, "Duloxetine," for more information.(A1)

Estrogen: Topical application of estrogen to the vaginal area increases urethral blood flow and enhances the sensitivity and density of alpha-adrenergic receptors. Estrogen does not directly affect urethral continence.[67] Local estrogen is safe and effective in the treatment of genitourinary syndrome of menopause and has been shown to improve urinary symptoms in postmenopausal patients with incontinence.[68] The optimal dose, duration of treatment, long-term effects, and cost-effectiveness are still unknown and require ongoing study.[68] However, a commonly used protocol is 1 g or less applied vaginally, 2 or 3 times weekly. Please see StatPearls' companion resources, "Vaginal Atrophy" and "Estrogen," for more information. (B2)

Tricyclic antidepressants: These medications have alpha-adrenergic effects that aid in urethral constriction and closure. Imipramine hydrochloride and doxepin, in particular, have been shown to reduce bladder contractility and increase urethral resistance.[67] The adverse effect profile of tricyclic antidepressants has significantly limited their use in treating patients with stress incontinence. Some common adverse effects include fatigue, hypotension, sedation, agitation, blurred vision, and sexual dysfunction.[67] Please see StatPearls' companion resources, "Imipramine" and "Doxepin," for more information. 

Surgery

The primary goals of surgery for patients with stress incontinence include reinforcing the pubourethral ligaments and the paraurethral connective tissue at the mid-urethra area. Surgical treatment is comprised of abdominal procedures, such as open or laparoscopic; vaginal procedures; and urethral compression devices, such as slings, artificial sphincters, and urethral bulking agents. Urethral slings have become the most common type of surgery to correct stress urinary incontinence. There is no single surgical procedure for the treatment of all patients with stress incontinence. The surgery must be tailored for the patient, not the reverse.

An abdominal approach is indicated in cases where there is a large uterus compressing the bladder, necessitating a concomitant hysterectomy, in the absence of vaginal prolapse, when adnexal pathology is present, or following failed vaginal incontinence surgery. Vaginal surgery should be considered when vaginal prolapse is present, a history of failed abdominal surgery, or the patient is at high risk for abdominal surgery due to factors such as multiple abdominal incisions and morbid obesity. If significant uterine procidentia exists, a vaginal hysterectomy should be performed, followed by retropubic suspension. If pelvic pressure symptoms exist with stress incontinence, the surgeon must assess for and correct associated conditions such as cystocele, enterocele, or rectocele through an anterior repair, enterocele repair, or posterior colpoperineoplasty, respectively.

A prophylactic incontinence procedure should be considered for females with prolapse without stress urinary incontinence, given postoperative voiding dysfunction may occur with an anterior colporrhaphy alone.

Abdominal incontinence surgeries:

Marshall-Marchetti-Krantz (MMK) procedure: This procedure is a retropubic approach elevating and fixating the anterolateral part of the urethra to the posterior pubic symphysis and adjacent periosteum of the pubic bone. The Marshall Marchetti Krantz procedure can be considered either as a primary or secondary treatment for incontinence and may be used as an adjunct to vaginal vault repair for prolapse.[69][70](A1)

Burch colposuspension: In this procedure, the bladder neck is supported by placing a few stitches on either side of the urethra and securing them to the iliopectineal (Cooper) ligament. This surgery can be performed as an open or laparoscopic procedure and is believed to be especially helpful for patients with demonstrable urethral hypermobility.[71] 

Pubovaginal sling: A strip of rectus fascia or fascia lata is placed directly under the bladder neck through the retropubic space and secured at the level of the rectus abdominis fascia. Fayyad et al introduced a new surgical technique, the laparoscopic mid-urethral autologous rectus fascial sling, for patients with stress urinary incontinence. This method offers several advantages, including a minimally invasive approach, precise suture placement under laparoscopic guidance, and the prevention of sling over-tightening.[72]

Vaginal and other surgeries:

Modified Pereyra procedure (MPP): This procedure involves the elevation of paraurethral tissue to the abdominal wall, creating a significant elevation of the urethrovesical angle. The MPP can also be considered either as a primary or secondary treatment and may be an adjunct to vaginal vault repair for prolapse.[69][73] (A1)

Mid-urethral sling procedure: This procedure involves placing a synthetic or autologous material under the mid-urethra, the most critical female continence zone. An open-weave polypropylene mesh was originally used, stabilizing and promoting collagen ingrowth over time. In 2011, the US Food and Drug Administration (FDA) recommended against the use of synthetic vaginal mesh due to rare but serious complications such as chronic pain, mesh erosion, and extrusion.[74][75] (B3)

Amid the FDA recommendation and highly publicized litigation, organic materials and non-mesh options are generally preferred. These concerns regarding synthetic mesh in sling procedures spurred new interest in using autologous tissue.[76] Similar efficacy and complication rates at 12 months were found between patients with autologous slings and those using synthetic materials.[77] (A1)

According to a systemic review and meta-analysis, a higher BMI during mid-urethral sling surgery is an apparent risk factor for short- and long-term sling failure compared to individuals with normal weight.[78][79](A1)

Tension-free vaginal tape: The sling or tape insertion is inserted through the retropubic space and exits out the abdominal wall suprapubically. Advantages of the tension-free vaginal tape sling include rapid procedure completion in as little as 30 minutes with same-day patient discharge, no postoperative urinary catheterization, short recovery time, high success rates, and minimal pain.[80] However, the blind retropubic passage of trocars may cause inadvertent bladder trauma and, rarely, severe injury to the bowel or iliac vessels.[81][82][83](A1)

Transobturator tension-free vaginal tape: This technique involves placing the sling from the vagina through the obturator foramen and out through the skin of the groin. Compared to the standard tension-free vaginal tape procedure, it offers a reduced risk of bladder perforation or bowel injury, an even shorter operating time, and a quicker return to routine activities.[81] However, there may be an increased risk of bleeding from the medial branches of the obturator vessels.

A recent meta-analysis comparison of the various tension-free tape-based surgical procedures for stress incontinence found similar success rates, with the standard transvaginal tension-free vaginal tape procedure having the highest subjective cure rate.[80] However, it also produced a higher incidence of dyspareunia postoperatively and more vaginal mucosal perforations.[80](A1)

Injection of urethral bulking agents: This procedure involves inserting various materials, such as autologous fat, cross-linked collagen, ethylene vinyl alcohol copolymer, glutaraldehyde calcium hydroxylapatite, polydimethylsiloxane, and pyrolytic carbon-coated beads, directly into the proximal urethral mucosal layer. These agents support, constrict, coapt, and tighten the bladder neck opening, making the procedure particularly useful for managing intrinsic sphincter deficiency. Multiple bulking agents exist, each with unique biophysical properties, efficacy, and safety issues, and no particular agent has proven superior.[84] Collagen is the most commonly used agent, with a reported success rate exceeding 50%.[85] Improved nonabsorbable, non-migrating agents are now commercially available.[86][87] Two agents have been removed from the market due to injection site reactions (dextranomer hyaluronic acid) and migration problems (polytetrafluoroethylene).[85] (A1)

This procedure is performed in an office setting with local anesthesia, and 2 to 3 injections may be required to improve symptoms.[88] Urethral bulking is generally recommended for patients where less invasive methods have failed and are unwilling or unable to undergo anit-incontinence surgery.[89][90] Although less invasive than incontinence surgical procedures, the urethral bulking procedure is also less effective. The risks include urinary retention, migration of the bulking agent (locally and to regional lymph nodes), systemic absorption, fibrosis, embolization, abscess formation, vaginal erosion, allergic reactions, and continuing or recurrent leakage.[91](A1)

Urethral bulking is not a first-line option for stress incontinence in men due to limited studies demonstrating efficacy, increased complications, lack of a standardized technique, uncertainty about the optimal volume of bulking material, and an unclear ideal injection site.[92][93][94](A1)

Cadaver studies suggest that urethral bulking agents may be effective for men with stress incontinence if these technical issues and other problems can be solved.[92] Currently, bulking agents are not generally recommended for men with stress urinary incontinence outside of clinical trials but may be considered for selected individuals with relatively minimal leakage who understand the risks and are unfit or unwilling to accept more invasive surgery.[92][93][94](A1)

Male incontinence surgeries:

Male urinary slings: These are typically used for men with mild-to-moderate stress incontinence (defined as using no more than 4 pads per day, with 2 pads or fewer being optimal) who are unresponsive to nonsurgical treatments.[95] Those with more severe incontinence are advised to consider an artificial sphincter instead.[92] Potential patients should optimally not have any prior history of pelvic radiation and minimal post-void residual urine volumes. They should be able to demonstrate some degree of voluntary external sphincteric function, which can be assessed through urodynamics or cystoscopy. Urodynamics confirms that the detrusor can generate sufficient voiding pressure to overcome the added outflow resistance provided by the sling, and preoperative cystoscopy is performed to rule out any abnormal anatomy, lesions, or strictures.[95] (B3)

The surgery is typically performed in an outpatient setting. The sling material is surgically positioned below the anterior urethra, compressing the bulbous urethra to promote urethral coaptation and prevent urinary leakage.[95] The procedure also reorients and realigns the proximal urethra with the external sphincter, further enhancing continence.[95] Various sling types are now available, including adjustable models that permit postoperative adjustment.[95](B3)

Patients are advised to avoid heavy lifting, strenuous exercise, squatting, and climbing ladders for at least 3 months after the surgery, as these activities may loosen the sling. In selected patients, the vast majority (about 80%) experience significant improvement in incontinence, and most may not require pads. Please see StatPearls' companion resource, "Slings for Male Incontinence," for more information.

Adjustable dual-balloon implanted continence device therapy for men: This therapy involves the implantation of 2 individual periurethral silicon balloons percutaneously implanted on either side and slightly distal to the bladder neck. These balloons provide passive compression that is adjustable postoperatively for optimal results.[92][96][97] The size of the balloons and their degree of urethral compression can be adjusted by adding or removing fluid through a titanium scrotal access port.[92][97] Adjustments are easily made in the clinic with only local anesthetic. The procedure itself is considered minimally invasive and is a reasonable alternative to an artificial sphincter for patients with moderate-to-severe stress incontinence due to postoperative intrinsic sphincter deficiency with a duration of at least 1 year.[92] Overall success is reported in recent meta-analyses as complete dryness in 55% to 60% and more than 50% leakage improvement in 82%, but with a reoperation rate of 23%, typically to replace a leaking balloon, device erosion, or dislocation.[92][98][99][100](A1)

As with male slings, it is necessary to perform urodynamics and ensure the bladder muscle can generate adequate voiding pressure before balloon implantation. A history of pelvic radiation and severe stress incontinence are relative contraindications.[101][99] Prior radiation therapy reduces the success rate of the procedure by one-third.[102] Although adjustable dual-balloon implanted continence therapy is not FDA-approved for females with stress incontinence in the United States, it is being used successfully for this purpose in South America and Europe. Please see StatPearls' companion resource, "Artificial Urinary Sphincters and Adjustable Dual-Balloon Continence Therapy in Men," for more information.(A1)

Artificial urinary sphincters: These are mechanical medical devices that essentially place a constricting cuff around the urethra.[92] The cuff is controlled (opened) by a hand-operated pump implanted under the skin (in the labia majora in females or the scrotum in males). The device is typically used as a treatment of last resort in cases of severe incontinence (more than 4 pads daily), most often in males with severe post-prostatectomy stress urinary incontinence.[92] Patients must have sufficient cognitive ability, dexterity, and manual strength to operate the device, and the bladder must empty completely for effective use. The device can be implanted through an open or laparoscopic approach.[92]

Some patients may be discharged on the same day of the procedure, while others may require an overnight hospital stay.

The device is deliberately left inactive for at least 1 month after surgery to allow for adequate healing and tissue revascularization. Heavy lifting and similar activities are discouraged after the procedure. In follow-up, patients are trained to operate the device, which is then activated.

High success rates (over 90% in properly selected patients) and good functional outcomes with patient satisfaction rates up to 90% have been reported.[92][103][104] Some newer devices incorporate smart technology and have already been used clinically. Please see StatPearls' companion resource, "Artificial Urinary Sphincters and Adjustable Dual-Balloon Continence Therapy in Men," for more information.(B3)

Differential Diagnosis

When evaluating a patient for stress urinary incontinence, it is essential to consider other potential causes of urinary leakage to ensure accurate diagnosis and effective treatment. Obtaining a detailed history and a thorough physical examination are crucial for excluding other differential diagnoses. Urodynamic testing may be the next step if the diagnosis is unclear or complicated.

A broad list of differential diagnoses that should be considered when assessing a patient presenting with symptoms of stress urinary incontinence including the following:

• Bladder stones
• Bladder tumors
• Congenital anomalies, such as ectopic ureter and epispadias
• Fistulas following surgery or radiation
• Functional incontinence (no organic cause)
• Genitourinary syndrome of menopause or other etiologies of estrogen deficiency
• Interstitial cystitis
• Neurologic causes, including stroke, multiple sclerosis, Parkinson disease, senile dementia, meningomyelocele, and spinal injury
• Pelvic masses compressing the bladder
• Prolapse
• Pharmacologic causes, including diuretics, parasympathomimetics, antidepressants, and phenothiazines
• Post-infection fibrosis
• Radiation
• Systemic medical causes, such as hypothyroidism, diabetes, and depression
• Urinary tract infection, such as bacterial, chlamydial, or tuberculosis

In addition, there are 3 other types of incontinence to consider along with stress urinary incontinence: [105]

• Mixed incontinence: Involuntary loss of urine with components of both urge and stress incontinence. Please see StatPearls' companion resources, "Urinary Incontinence" and "Mixed Urinary Incontinence," for more information.

• Overflow incontinence: Continuous urinary leakage or dribbling from urinary retention. Please see StatPearls' companion resources, "Female Urinary Retention" and "Male Urinary Retention: Acute and Chronic," for more information.[77]

• Urge incontinence: Involuntary loss of urine associated with urgency or a sudden, compelling desire to void that is difficult to defer. Please see StatPearls' companion resource, "Urge Incontinence," for more information.

Prognosis

Stress urinary incontinence can significantly impact a patient's quality of life. Treatment aims to improve the quality of life for those affected. Complete resolution of stress incontinence may not always be feasible, and a combination of behavioral, pharmacological, and surgical treatments may be necessary. Some patients may be satisfied with improved incontinence symptoms even without complete resolution, especially if it avoids surgery.

The prognosis of stress incontinence varies depending on the nature and severity of the condition, the effectiveness of treatment, and individual factors such as age and overall health. Generally, with appropriate management, many individuals with stress incontinence experience significant improvement in symptoms and quality of life. Conservative treatments such as pelvic floor muscle exercises (Kegels), behavioral modifications, and lifestyle changes often yield positive outcomes, particularly when initiated early.

Lifestyle modifications alone can be helpful. For instance, it has been reported that a weight reduction of just 8% through exercise led to nearly a 50% decrease in the frequency of incontinence episodes.[106] Cure rates with pelvic floor muscle exercises have been reported to be 58.8% at 12 months.[107] 

The effect of pelvic floor exercise on sexual function has been studied. Although pelvic floor muscle training proved to effectively treat stress incontinence, no improvement was demonstrated regarding sexual function.[108] Vaginal pessaries may improve symptoms in 33% of patients.[109]

There is equivocal evidence that estrogen is efficacious in the treatment of patients with stress urinary incontinence. Topical estrogen may also help increase blood flow to paraurethral receptors and thicken an atrophic vagina if planning vaginal surgery.[110][111] Symptom control with anticholinergics has been reported to be 49%.[107]

Surgical interventions can improve continence and provide long-term relief for individuals who do not respond adequately to conservative measures. Overall, surgical treatment has a cure rate of 84%, regardless of the technique used. The quality of life is improved postoperatively for stress urinary incontinence patients with or without concomitant pelvic organ prolapse.[112] The literature includes many studies comparing cure, improvement, and failure rates between the various surgical procedures for stress incontinence, and no single surgical procedure has been proven definitively superior.

A randomized trial found no difference in success rates between the Burch colposuspension and the retropubic mid-urethral sling at 6 months and 5 years.[113] Five-year follow-up studies of tension-free vaginal tape have found cure rates of 57.4% to 83%, improvement rates of 7.6% to 17%, and failure rates of 9.1% to 25.6%.[114][115] 

Artificial urinary sphincter implantation was more effective compared to slings for males with moderate stress incontinence, but patient selection is critical. No significant differences were found in complication rates between the 2 procedures.[116]

Another study compared the outcomes of the MPP and the MMK, finding similar results. The study reported that 84% of MPP patients were cured compared to 86.6% of MMK patients.[69] In the same study, 9.8% of MPP patients improved compared to 6.6% of patients treated with MMK, and 6.2% of MPP patients failed to improve post-surgery compared to 6.8% of MMK patients.[69]

Urethral bulking injections have reported cure rates between 24.8% and 36.9% at 12-month follow-up.[107]

As with any medical condition, the prognosis of stress urinary incontinence can be heavily influenced by underlying health conditions, the presence of comorbidities, and patient compliance with treatment and lifestyle recommendations. Regular follow-up and ongoing management are crucial for monitoring progress, adjusting treatment plans as required, and optimizing long-term outcomes for individuals affected by stress urinary incontinence. Surgical failures are often the result of an inadequate preoperative evaluation of all causes of the patient's incontinence or a failure to optimize patient risk factors, such as obesity and smoking.

Complications

Stress urinary incontinence can lead to numerous complications that significantly impact a patient's quality of life. Physically, the constant leakage of urine can cause skin irritation, rashes, and infections in the perineal area, leading to discomfort and further health issues. Socially and psychologically, significant stress urinary incontinence can result in public embarrassment, anxiety, and social withdrawal, as individuals may avoid activities that could trigger incontinence episodes. This social isolation can contribute to depression and a decreased sense of well-being. In addition, the financial burden from constantly purchasing incontinence products, medical treatments, and potential loss of work productivity can strain personal resources.

Medications can also lead to complications. The most frequently encountered adverse effects of anticholinergics are dry mouth and constipation. Anticholinergics can also aggravate existing cardiac arrhythmias and worsen narrow-angle glaucoma.[117] 

The most common complications following surgical management include voiding difficulty and urinary retention, urinary tract infection, postoperative dyspareunia, mesh erosion, pelvic organ prolapse, device failure or migration, and persistent or recurrent urinary incontinence.[118] Injury to the gastrointestinal or genitourinary tract, such as bowel and bladder perforation, and significant bleeding, can occur as a result of surgery.[119][120]

In some cases, complications of stress incontinence can lead to potentially more serious renal complications. Therefore, timely and effective management of stress incontinence is crucial to mitigate these complications and enhance the patient's overall health and quality of life.