What is an anovaginal fistula?
An anovaginal fistula is an abnormal connection (tract) between the anal canal and the vagina. This allows air, stool, or pus to pass from the bowel into the vagina, causing discomfort and infections.
Fistulas usually do not heal on their own and require medical treatment or surgery to repair the abnormal connection.
Causes of an anovaginal fistula
An anovaginal fistula may occur due to:
- An anal abscess that bursts into the vagina
- Childbirth injuries, especially after a difficult delivery
- Surgery complications, such as after bowel or gynaecological surgery
- Crohn’s disease or other inflammatory bowel conditions
- Cancer, particularly in the bowel, anus, or reproductive organs
Symptoms of an anovaginal fistula
If you have an anovaginal fistula, you may experience:
- Passing wind through the vagina
- Leaking stool through the vagina
- Pus or blood coming from the vagina
- Vaginal irritation or discomfort
- Repeated urinary tract infections (UTIs)
If you notice any of these symptoms, speak to your doctor as early treatment can help prevent further complications.
How is an anovaginal fistula diagnosed?
Your doctor will take a detailed medical history and perform a physical examination. They may also recommend further tests, such as:
- Rigid sigmoidoscopy or proctoscopy – A small tube is inserted into the rectum to examine the bowel and locate the fistula opening
- MRI scan – Provides detailed images of the fistula and surrounding tissues. This is useful if the fistula is deep or difficult to see
- Endoanal ultrasound and anorectal physiology tests – Helps assess damage to the anal sphincter muscles, especially if childbirth or surgery caused the fistula
- Examination under anaesthetic (EUA) – If the area is too painful to examine while awake, your doctor may recommend a short procedure under anaesthesia to confirm the diagnosis and possibly begin treatment
- Flexible sigmoidoscopy or colonoscopy – If you are over 40 years old and have bleeding or changes in bowel habit, your doctor may suggest examining the bowel to rule out any other conditions
How is an anovaginal fistula treated?
Most anovaginal fistulas will not heal without surgery. The main goals of treatment are to:
- Close the fistula and restore normal function
- Avoid damage to the anal sphincter muscles, which help control bowel movements
Surgery for an anovaginal fistula can be complex, as it passes close to or through the anal sphincter muscles. The type of surgery depends on the size and location of the fistula.
Surgical options may include:
- Advancement flap repair – Healthy tissue from the rectum or vagina is used to cover the fistula opening
- Sphincter repair – If the fistula has affected the anal sphincter, a sphincter repair may be performed at the same time
- Seton placement – A thin surgical thread is placed in the fistula to help drain infection before a permanent repair is done
- Colostomy (temporary stoma) – In severe cases or where the fistula keeps coming back, a temporary colostomy (diverting stool away from the affected area) may be needed before further surgery
Your surgeon will discuss the best treatment approach with you, depending on your symptoms, medical history, and test results.
Why choose the Midlands Bowel Clinic?
- Specialist colorectal surgeons with extensive experience in treating complex fistulas
- Advanced diagnostic tools, including MRI, ultrasound, and endoscopy for accurate assessment
- Personalised treatment plans tailored to your condition and lifestyle
- Comprehensive aftercare and follow-up support to ensure a smooth recovery
Contact us
If you are experiencing symptoms of an anovaginal fistula or have been advised to seek treatment, contact the Midlands Bowel Clinic. We are here to help.
