OVERVIEW

What is a vaginal fistula?

Normally, the vagina only connects to the uterus. A vaginal fistula refers to an abnormal passage between the vagina and adjacent organs caused by various factors, including vesicovaginal fistula, urethrovaginal fistula, ureterovaginal fistula, and rectovaginal fistula.

When a vaginal fistula occurs, urine, feces, or other foreign matter may leak from the vagina, often producing an unpleasant odor and soaking clothes or bedding, significantly impacting health and quality of life. However, vaginal fistulas can be cured through surgery.

What are the types of vaginal fistulas?

• Based on symptoms, they can be classified as: urinary fistula, fecal fistula, or mixed fistula.
• Based on the location of the fistula:
• Vesicovaginal fistula: A connection between the vagina and bladder, causing urine leakage from the vagina.
• Urethrovaginal fistula: A connection between the vagina and urethra. If the fistula is below the urethral sphincter, urine leakage may be controllable.
• Ureterovaginal fistula: A connection between the vagina and ureter, leading to continuous urine leakage.
• Rectovaginal fistula: A connection between the vagina and rectum, potentially causing fecal leakage and forming a fecal fistula.

SYMPTOMS

What are the main manifestations of urinary fistula in vaginal fistula?

The main symptom is urine leakage from the vagina. Persistent vaginal fluid discharge after childbirth or pelvic surgery is the most common and typical clinical manifestation. Depending on the location of the fistula, the manifestations may vary:

• If the fistula is located at the lowest part of the bladder (trigone or bladder neck), it manifests as continuous urine leakage.
• If the fistula is located above the trigone (high-position vesicovaginal fistula), it often presents as positional urine leakage, with no leakage while standing but leakage when lying down.
• Small bladder fistulas may only leak when the bladder is full, known as overflow incontinence.
• For urethrovaginal fistulas located below the urethral sphincter (lower third of the urethra), patients can generally control urination, but urine leaks through the vagina during voiding.
• In cases of unilateral ureterovaginal fistula, in addition to normal urination, there may also be paroxysmal urine leakage from the vagina.

Can vaginal fistula cause redness and rashes on the vulva, inner thighs, and buttocks?

Yes, it is possible due to prolonged urine irritation. Superficial ulcers may also occur, accompanied by vulvar itching and burning pain, often with urinary tract infections.

Do patients with rectovaginal fistula always pass stool through the vagina?

Not necessarily.

When the fistula is large, formed stool may pass through, while loose stool leads to continuous leakage. If the fistula is small, no stool may pass through the vagina, but intestinal gas may escape through the fistula, and loose stool may leak from the vagina.

When does urine leakage occur in vaginal fistula?

The timing of urine leakage depends on the cause:

• For cases caused by tissue necrosis due to prolonged labor and fetal head pressure, leakage usually occurs 3–7 days postpartum.
• For surgical injuries not repaired immediately, leakage occurs right after surgery.
• Leakage from laparoscopic hysterectomy often occurs 1–2 weeks postoperatively.
• In radical hysterectomy patients, injuries usually lead to leakage 10–21 days postoperatively, mostly ureterovaginal fistulas.
• Radiation-induced leakage occurs later and is often combined with fecal fistula.

Does vaginal fistula affect normal sexual life?

Vaginal fistula severely impacts patients' physical and mental health. Due to constant urine leakage or fecal discharge during diarrhea, unpleasant odors often develop, soaking clothes or bedding, significantly affecting health and quality of life.

Patients commonly experience depression, low self-esteem, anxiety, loss of interest in sex, reduced libido, and orgasmic dysfunction. Severe vaginal scarring may also lead to dyspareunia or painful intercourse. Women with rectovaginal fistula may pass gas or fluid through the vagina during intercourse. Their partners may also develop psychological issues.

For these reasons, marital intimacy becomes difficult, leading to emotional distress. Some patients may develop severe psychological disorders, even suicidal tendencies.

The primary treatment for vaginal fistula is surgery. If cured, patients' mental and physical health can improve, allowing them to return to normal life.

CAUSES

What are the main causes of urinary fistula?

• Obstetric trauma: In the past, obstetric trauma was the primary cause of urinary fistula. Based on the pathogenesis, it can be divided into:

  • Necrotic urinary fistula: Caused by a narrow pelvis, oversized fetus, or abnormal fetal position leading to cephalopelvic disproportion. Prolonged labor, especially when the anterior vaginal wall, bladder, and urethra are compressed between the fetal head and the pubic symphysis (during the second stage of labor), results in local tissue ischemia and necrosis, forming a fistula.
  • Traumatic urinary fistula: Caused by direct injury during obstetric procedures, particularly forceps-assisted delivery. Traumatic fistulas are far more common than necrotic fistulas.

• Gynecological surgery: Both abdominal and vaginal surgeries can lead to urinary fistula. This usually occurs when separating adhesions damages the bladder or ureter, or when excessive dissection of the distal ureter causes ischemia, resulting in vesicovaginal or ureterovaginal fistula.

• Other causes: Trauma, radiation therapy, bladder tuberculosis, genitourinary tumors, improper placement of a pessary, local drug injections, etc., can also cause urinary fistula.

• Congenital vaginal fistula.

What are the main causes of fecal fistula?

• Obstetric trauma: Prolonged pressure of the fetal head on the vagina can lead to rectal necrosis and fistula formation. Rough obstetric maneuvers, surgical injuries causing third-degree perineal tears, failed rectal healing after repair, or sutures penetrating the rectal mucosa during perineal tear closure can also result in rectovaginal fistula.

• Pelvic surgery: Procedures like hysterectomy, especially in cases of severe pelvic adhesions, may damage the rectum. Fistulas typically occur in the vaginal fornix (posterior and distal part of the vagina).

• Inflammatory bowel disease: Conditions like Crohn's disease or ulcerative colitis are another major cause of rectovaginal fistula. While inflammatory bowel disease often affects the small intestine, the colon and rectum can also be involved.

• Surgery for congenital genital tract anomalies: These procedures carry a higher risk of rectovaginal fistula.

• Other causes: Long-term pessary use without removal, late-stage malignant tumor infiltration, radiation therapy, etc., can also lead to fecal fistula.

• Congenital rectovaginal fistula.

DIAGNOSIS

How to Diagnose a Vaginal Fistula?

A preliminary diagnosis can be made based on medical history and gynecological examination. To further determine the location and size of the fistula, the condition of surrounding scar tissue, the presence of urethral stricture, and the function of both kidneys, tests such as the methylene blue test, cystoscopy, indigo carmine test, and intravenous pyelography should be performed.

Larger rectovaginal fistulas can be confirmed by digital rectal examination, while smaller fistulas can be located using a probe.

CT urography can also clearly visualize the entire renal pelvis, ureters, and bladder.

What Is the Methylene Blue Test?

Cotton balls are placed sequentially at the vaginal apex, mid-third, and distal end. The bladder is then filled with 300 mL of diluted methylene blue solution (a harmless blue dye). The cotton balls are removed one by one, and the location of the fistula is estimated based on dye staining:

• If blue dye leaks from a small opening in the vaginal wall, it indicates a vesicovaginal fistula.
• If the cotton balls remain unstained or show yellow staining, a ureterovaginal fistula is suspected.

If no blue staining is observed but clinical suspicion remains, the cotton balls may be repositioned, and the patient is asked to walk for 30 minutes before rechecking for staining.

What Tests Are Needed to Diagnose a Rectovaginal Fistula?

• To locate the fistula, a probe is inserted into the fistula tract, or a rectal examination is performed. Fistulography may be necessary to confirm the fistula's position.

• Vaginal digital examination: Sometimes, the fistula can be palpated on the posterior vaginal wall.

• Vaginal speculum examination: Large fistulas may be visible upon speculum exposure, while smaller fistulas may appear as a small, bright red granulation tissue.

• Methylene blue injection test: A gauze is placed in the vagina, and 10 mL of methylene blue is injected into the rectum. After a few minutes, the gauze is checked for blue staining to confirm the presence of a fistula.

• Probe examination: A uterine probe is inserted through the vaginal fistula, and the tip can be felt by a finger inserted into the anus.

• Barium enema: If a rectovaginal fistula is present, barium may flow into the fistula tract.

TREATMENT

Which department should I visit for vaginal fistula?

Gynecology or obstetrics and gynecology.

How is vaginal fistula treated?

• For urinary fistula patients, doctors will first perform scar excision around the fistula opening and suture repair. After surgery, ensure unobstructed bladder drainage, retain a urinary catheter for 8–12 days, and use antibiotics to prevent infection.

• Fecal fistula patients also require surgical treatment. For larger fistula openings or severe scarring, a colostomy is performed first.

When is the best time for surgery for urinary tract vaginal fistula?

• Directly damaged urinary fistulas should be surgically repaired as soon as possible.
• For fistulas caused by other reasons, wait for 3 months until tissue edema subsides and local blood supply returns to normal before surgery.
• After a failed fistula repair, wait at least 3 months before another surgery.
• For radiation-induced urinary fistulas, it may take longer for scar tissue to form, so repair is recommended after 12 months.

When is the best time for surgery for fecal fistula?

• Congenital fecal fistulas should be surgically treated after the patient reaches menstruation around age 15. Surgery too early may cause vaginal stenosis.
• For pressure necrosis-induced fecal fistulas, wait 3–6 months before surgical repair.

What preparations are needed before surgery for rectovaginal fistula with fecal leakage?

• Bowel preparation: Consume a liquid diet for 3 days before surgery and take oral intestinal antibiotics. Perform cleansing enemas the night before and the morning of surgery.
• Vulvar and vaginal preparation: For 3 days before surgery, use a 1:5,000 potassium permanganate sitz bath and disinfect the vulva and vagina with cotton balls.

Is surgery always necessary for vaginal fistula?

Not necessarily. For example:

• Small bladder vaginal fistulas occurring shortly after childbirth or surgery may heal naturally with continuous catheter drainage to fully empty the bladder.
• For recent ureterovaginal fistulas, inserting a ureteral catheter under cystoscopy to drain urine from the affected kidney, along with antibiotics to prevent infection, may allow natural healing.

What postoperative precautions should be taken after urinary fistula surgery?

• For the first 5 days post-surgery, consume liquid or low-residue semi-liquid diets to avoid bowel movements.

• On the fourth day after surgery, administer liquid paraffin to aid bowel movements and prevent constipation, which could strain the repaired incision.

What should pregnant patients with vaginal fistula do?

Fistula repair should be performed after childbirth when menstruation has normalized.

Can vaginal fistula repair surgery be performed during menstruation?

It is generally performed 3–7 days after menstruation ends. If the initial repair fails, the timing for repeat surgery remains the same.

Can rectovaginal fistula recur after surgery?

Rectovaginal fistula is a connection between the rectum and vagina, often occurring due to congenital anorectal malformations. Since the rectum and vaginal posterior wall share a 9 cm boundary, trauma or inflammation can cause fistulas anywhere along this area. Recurrence is possible and relatively common, but repeat surgery can be performed.

Can pregnancy occur without surgery for rectovaginal fistula?

It is not advisable. Surgical treatment is recommended to avoid vaginal infections that may affect conception or cause miscarriage.

Should congenital rectovaginal fistula surgery be performed as early as possible?

No. Surgery should be performed after menstruation begins around age 15 to prevent vaginal stenosis.

Can vaginal fistula be treated with minimally invasive surgery (laparoscopic surgery)?

This depends on the fistula's location, size, and other factors.

• Low-positioned vaginal fistulas can be repaired transvaginally, which is less invasive, has fewer complications, and allows repeat repairs.
• High-positioned fistulas may require transabdominal surgery.
• For large or complex fistulas, a combined transvaginal and transabdominal approach may be needed. Transabdominal surgery can be performed laparoscopically, such as laparoscopic repair of bladder vaginal fistula or high rectovaginal fistula, with successful cases reported.

DIET & LIFESTYLE

What are the dietary precautions after rectovaginal fistula surgery?

• For rectovaginal fistula, it is advisable to consume more foods rich in protein and vitamins to meet the nutritional needs for wound healing.
• Avoid smoking and drinking alcohol.

Does vaginal fistula affect fertility?

The main impact of vaginal fistula is the potential risk of infection. Without infection, it does not affect pregnancy. However, if it causes bacterial infection in the vagina or even retrograde infection in the uterus, it may impact fertility.

Can patients with vaginal fistula deliver vaginally?

No. Vaginal delivery may lead to fetal infection and risks worsening or tearing the fistula.

PREVENTION

How to Prevent Vaginal Fistula?

Most urinary fistulas can be prevented. Paying attention to potential risk factors and preventing obstetric-related urinary fistulas is key.

• For suspected injuries, insert a urinary catheter for 10 days to keep the bladder empty, promoting blood circulation recovery in compressed areas and preventing fistula formation.
• During gynecological surgery, if severe pelvic adhesions, extensive malignant tumor infiltration, or other challenging conditions are anticipated, preoperative ureteral catheter placement via cystoscopy can aid intraoperative identification.
• Even in straightforward total hysterectomies, clear anatomical identification is essential before proceeding. Immediate repair is necessary if ureteral or bladder injury is detected during surgery. If ureteral injury is suspected, prompt insertion of a ureteral catheter or double-J stent for drainage is advised. Uterine pessaries must be removed periodically.
• During cervical cancer radiotherapy, ensure proper placement and fixation of vaginal radiation sources, avoiding excessive radiation doses.

Despite surgeons' utmost care, urinary fistulas cannot be entirely ruled out, and patients should still consider this risk.

Prevention of fecal fistulas: The principles are similar to those for urinary fistulas. During delivery, protect the perineum to prevent severe lacerations. After perineal suturing, perform a routine rectal examination. If sutures penetrate the rectal mucosa, remove and re-suture immediately.