Rectovaginal Fistula

What is Rectovaginal Fistula?

A rectovaginal fistula is an abnormal connection between the lower portion of your large intestine — your rectum — and your vagina. Bowel contents can leak through the fistula, allowing gas or stool to pass through your vagina.

A rectovaginal fistula may result from:

  • Injury during childbirth
  • Crohn’s disease or other inflammatory bowel disease
  • Radiation treatment or cancer in the pelvic area
  • Complication following surgery in the pelvic area

The condition may cause emotional distress and physical discomfort, which can impact self-esteem and intimacy.

Symptoms

Depending on the fistula’s size and location, you may have minor symptoms or significant problems with continence and hygiene. Signs and symptoms of a rectovaginal fistula may include:

  • Passage of gas, stool or pus from your vagina
  • Foul-smelling vaginal discharge
  • Recurrent vaginal or urinary tract infections
  • Irritation or pain in the vulva, vagina and the area between your vagina and anus (perineum)
  • Pain during sexual intercourse

Causes

A rectovaginal fistula may form as a result of:

  • Injuries during childbirth. Delivery-related injuries are the most common cause of rectovaginal fistulas. This includes tears in the perineum that extend to the bowel, or an infection of an episiotomy — a surgical incision to enlarge the perineum during vaginal delivery. These may happen following a long, difficult, or obstructed labor. These types of fistulas may also involve injury to your anal sphincter, the rings of muscle at the end of the rectum that help you hold in stool.
  • Crohn’s disease. The second most common cause of rectovaginal fistulas, Crohn’s disease is an inflammatory bowel disease in which the digestive tract lining is inflamed. Most women with Crohn’s disease never develop a rectovaginal fistula, but having Crohn’s disease does increase your risk of the condition.
  • Cancer or radiation treatment in your pelvic area. A cancerous tumor in your rectum, cervix, vagina, uterus or anal canal can result in a rectovaginal fistula. Radiation therapy for cancers in these areas can also put you at risk. A fistula caused by radiation usually forms within six months to two years after treatment.
  • Surgery involving your vagina, perineum, rectum or anus. Prior surgery in your lower pelvic region, such as removal of your uterus (hysterectomy), in rare cases can lead to development of a fistula. The fistula may develop as a result of an injury during surgery or a leak or infection that develops afterward.
  • Other causes. Rarely, a rectovaginal fistula may be caused by infections in your anus or rectum; infections of small, bulging pouches in your digestive tract (diverticulitis); long-term inflammation of your colon and rectum (ulcerative colitis); dry, hard stool that gets stuck in the rectum (fecal impaction); or vaginal injury unrelated to childbirth.

Complications

Physical complications of a rectovaginal fistula may include:

  • Uncontrolled loss of stool (fecal incontinence)
  • Hygiene problems
  • Recurrent vaginal or urinary tract infections
  • Irritation or inflammation of your vagina, perineum or the skin around your anus
  • An infected fistula that forms an abscess, a problem that can become life-threatening if not treated
  • Fistula recurrence

Among women with Crohn’s disease who develop a fistula, the chances of complications are high. These can include poor healing, or another fistula forming later.

Who to See and Types of Treatments Available

Doctors often diagnose the condition during physical examination and assessment of symptoms of rectovaginal fistula. However, additional diagnostic tests are performed to accurately assess its extent. These tests include:

  • Anorectal ultrasound to determine whether there are other problems caused by the fistula and to assess the anal sphincter
  • Blood and urine tests to check for infection
  • Imaging tests to locate the fistula and determine if other pelvic organs are also affected

Although rectovaginal fistulas are easy to diagnose, they are often difficult to cure and patience is required during the evaluation process to fully assess the extent of the condition.

After diagnosing a patient with rectovaginal fistula, it is a common practice for patients to undergo antibiotic therapy for up to three months for the treatment of any inflammation or infection. In some cases, this is enough for some fistulas to close on their own. However, most require a surgical procedure, which involves incising the fistula so it can heal. This can be done through the vagina or rectum (for low fistulas) or via an incision in the abdomen (for high fistulas located at the posterior fornix).

During a rectovaginal fistula repair, a sharp circumferential dissection is made to separate the vagina from the rectum. The entire fistulous tract and the small rim of the mucosa are then incised before the rectal wall is closed with incisions.

Rectovaginal fistula treatment also involves harvesting a tissue graft from other parts of the body or folding a flap of healthy tissue near the fistula to cover the opening. Surgeons also repair the anal sphincter muscles if they have been damaged.

Colostomy, a surgical procedure in which feces is diverted to a bag outside of the body to allow the rectum to heal, is also performed in recurrent or complex cases. This is done when there’s scarring caused by previous radiation treatment or surgery, tissue damage, cancerous tumours, significant fecal contamination, or abscess. If a colostomy is performed, treatment of rectovaginal fistula will take place as soon as the rectum has healed, which can take between eight and twelve weeks. After rectovaginal fistula surgery, the colostomy is reversed to restore normal bowel function.

While waiting for the repair of a rectovaginal fistula, patients are advised to practice good hygiene to prevent infection. They are also given antibiotics and medications to treat inflammation.