A rectovaginal fistula is an abnormal connection between the lower portion of your large intestine — your rectum — and your vagina. Contents of your bowel can leak from the fistula, meaning you might pass gas or stool through your vagina.
A rectovaginal fistula may result from an injury during childbirth, a complication following surgery, cancer or inflammatory bowel disease, such as Crohn’s disease. An estimated 0.1 percent of vaginal births lead to a rectovaginal fistula.
The symptoms of a rectovaginal fistula often cause emotional distress as well as physical discomfort. Though bringing up the subject with your doctor may be difficult, it’s important to have a rectovaginal fistula evaluated. Some rectovaginal fistulas may close on their own, but most need to be repaired surgically.
Depending on the size and location of the fistula, you may have very 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
- A 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 activity
- Urgent bowel movements or inability to control bowel movements
- Leakage of urine into your vagina if you also have a vesicovaginal fistula
A rectovaginal fistula may form as a result of:
- Injuries in childbirth. Obstetric injuries are the most common cause of rectovaginal fistulas. Such injuries include a tear in the perineum or an infection or tear of an episiotomy — surgical incision to enlarge the perineum. These may happen following a long, difficult labor. Fistulas arising from childbirth 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 a type of inflammatory bowel disease in which the lining of your digestive tract becomes inflamed. About 9 percent of women with Crohn’s disease develop a rectovaginal fistula.
- 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.
- Cancer or radiation treatment in your pelvic area. A cancerous tumor in your rectum, cervix, vagina, uterus or anal canal can cause a rectovaginal fistula. Radiation therapy for cancers in these areas can also put you at risk of developing a fistula. A fistula caused by radiation usually forms within two years following the treatment. Before the fistula forms, you may experience pain in your anus or rectum, bloody diarrhea, or bright red blood in your stool. If you spot these warning signs, your doctor will first rule out a return of cancer as the cause.
- Other causes. Less commonly, a rectovaginal fistula may be caused by infections in your anus or rectum, infections of small, bulging pouches in your digestive tract (diverticulitis) or vaginal trauma.
To figure out the cause of a rectovaginal fistula, your doctor will ask questions focused on possible risk factors and causes, including:
- Vaginal births
- Surgeries, cancer or radiation treatment in your pelvic region
- Inflammatory bowel disease, including Crohn’s disease
- Problems with bowel movements
In addition to talking with you, your doctor will perform a physical examination to try to locate the fistula and check for a possible tumor mass, infection or abscess. The exam includes a visual inspection of your vagina, anus and the area between them. Your doctor will perform a digital exam, inserting a gloved and lubricated finger into your vagina while feeling the perineum with another gloved finger, and then perform a rectal exam by inserting his or her gloved finger into your anus.
Unless the fistula is very low in the vagina and readily visible, your doctor may use a speculum to visualize the inside of the vagina. This may allow him or her to see the opening of the fistula inside your vagina. An instrument similar to a speculum, called a proctoscope, may be inserted into your anus and rectum to check the health of your rectum.
Tests for identifying fistulas
Often a fistula isn’t found during the physical exam. A variety of other tests may be used to locate and evaluate a rectovaginal fistula. These tests also help your medical team in planning for surgery.
- Water and blue staining tests. Filling the vagina with water and the rectum with air can help locate the fistula. Air passing from the rectum through the fistula forms bubbles on the vaginal side of the passage. Another test involves placing a tampon into your vagina, then injecting blue dye into your rectum. Blue staining on the tampon shows the presence of a fistula.
- Contrast tests. A vaginogram or a barium enema can help identify a fistula located in the upper rectum. These tests use a contrast material to show either the vagina or the bowel on an X-ray image.
- CT (computerized tomography). A CT scan is a special X-ray technique that provides more detail than a standard X-ray does. A CT scan of your abdomen and pelvis can help locate a fistula and determine its cause.
- MRI (magnetic resonance imaging). This test uses a magnetic field and radio waves to create images of soft tissues in your body. MRI can show the location of a fistula as well as involvement of pelvic organs or the presence of a tumor.
- Anorectal ultrasound. This procedure uses sound waves to produce a video image of your anus and rectum. Your doctor inserts a narrow, wand-like instrument into your anus and rectum. Anorectal ultrasound can evaluate the structure of your anal sphincter and may show defects caused by obstetric injury.
- Anorectal manometry. In this test, a narrow, flexible tube is inserted into your anus and rectum, then a small balloon at the tip of the tube is expanded. The test measures the sensitivity and function of your rectum and can provide useful information when a fistula is due to Crohn’s disease or radiation. This test does not locate fistulas but can help with planning repair.
- Other tests. If your doctor suspects you may have inflammatory bowel disease, he or she may order a colonoscopy. This test allows your doctor to view your colon using a thin, flexible, lighted tube with an attached camera. During the procedure, your doctor can take small samples of tissue (biopsy) for laboratory analysis, which can help confirm the diagnosis of Crohn’s disease. If you’ve received radiation therapy to your pelvic region, your doctor may do more small bowel tests, including X-rays, to make sure you don’t also have a small bowel fistula.
Physical complications of rectovaginal fistula may include incontinence, problems with hygiene, and irritation or inflammation of your vagina, perineum or the skin around your anus. In some cases, a fistula may become infected and form an abscess, a problem that can become life-threatening if not treated. Among women with Crohn’s disease who develop a fistula, the chance of another fistula forming later is high.
Treatment for a rectovaginal fistula depends on its cause, size, location and effect on surrounding tissues. Sometimes fistulas heal on their own, but most people need surgery to close or repair the abnormal connection. Before an operation can be done, the skin and other tissue around the fistula must be healthy, with no signs of infection or inflammation. Your doctor may advise a waiting period of up to three months before surgery to ensure the surrounding tissue is healthy and see if the fistula closes on its own.
An operation to close a fistula may be done by a gynecologist or a colorectal surgeon. The goal is to remove the fistula tract and close the opening by sewing together healthy tissue around it. The repair may require using a tissue graft taken from an adjacent part of the body, or folding a flap of healthy tissue over the fistula opening. More complicated operations may be needed if the anal sphincter muscles are also damaged or if there’s scarring or tissue damage from radiation or Crohn’s disease.
To clean out your bowel before the operation, you may take laxatives or follow a liquid diet for several days. This may be followed by an enema shortly before surgery. You’ll also be given an antibiotic medication before surgery.
In some cases, the surgeon may do a colostomy before repairing a fistula. A colostomy is an operation that diverts stool through an opening in your abdomen instead of through your rectum. This may be needed if you’ve had tissue damage or scarring from previous surgery or radiation treatment, an ongoing infection or significant fecal contamination, a cancerous tumor, or an abscess. If a colostomy is needed, your surgeon may wait eight to 12 weeks before repairing the fistula.
After an operation to close a fistula, you’ll be on a liquid diet for about three days, followed by a low-fiber diet for several weeks. A low-fiber diet reduces the frequency and volume of stools. Your care team may recommend that you take sitz baths two to three times a day and dry off with a blow dryer to keep the area clean and dry.
Some doctors suggest that a woman who’s had surgery to repair a fistula consider having a Caesarean delivery for the next pregnancy.
Good hygiene can help ease discomfort and reduce the chance of vaginal or urinary tract infections:
- Wash with water. Gently wash your outer genital area with warm water each time you experience vaginal discharge or passage of stool. Soap can dry and irritate your skin but may be necessary in moderation. Avoid rubbing with dry toilet paper. Premoistened, alcohol-free towelettes or wipes or moistened cotton balls may be a good alternative for cleaning the area.
- Dry thoroughly. Allow the area to air-dry after washing, or gently pat the area dry with toilet paper or a clean washcloth.
- Avoid irritants. These include harsh or scented soap and scented tampons and pads.
- Use a cold compress. Apply a cold compress, such as a washcloth, to the labial area.
- Apply a cream or powder. Moisture-barrier creams help keep irritated skin from having direct contact with fecal matter. Ask your doctor to recommend a product. Be sure the area is clean and dry before you apply any cream. Nonmedicated talcum powder or cornstarch also may help relieve discomfort.
- Wear cotton underwear and loose clothing. Tight clothing can restrict airflow, making skin problems worse. Change soiled underwear quickly. Products such as absorbent pads and disposable underwear can help if you’re passing liquid or stool. If you use pads or adult diapers, be sure they have an absorbent wicking layer on top.
- Don’t douche. Douching can increase your risk of infection.
Symptoms of a rectovaginal fistula can be very distressing, but treatment generally offers good results.