Endometriosis is a condition in which the tissue that normally lines your uterus — called endometrial tissue — grows and accumulates in other parts of your abdomen and pelvis.
During your menstrual cycle, this tissue can respond to hormones just as it does in your uterus. However, because it’s outside your uterus where it doesn’t belong, it can affect other organs, trigger inflammation, and cause scarring.
There are levels of severity for endometriosis:
- Superficial endometriosis. Smaller areas are involved, and tissue doesn’t grow very deeply into your pelvic organs.
- Deep infiltrating endometriosis. This is a severe level of the condition. Rectovaginal endometriosis falls under this level.
Rectovaginal endometriosis is one of the most severe and painful forms of the disease. The endometrial tissue can extend to two inches or more in depth. It can penetrate deep into the vagina, rectum, and the tissue that lies between the vagina and rectum, called the rectovaginal septum.
Rectovaginal endometriosis is less common than endometriosis in the ovaries or the lining of the abdomen. According to a review in the International Journal of Women’s Health, rectovaginal endometriosis affects up to 37 percent of women with endometriosis.
Some symptoms of rectovaginal endometriosis are the same as other types of endometriosis.
Symptoms of other endometriosis types include:
- pelvic pain and cramps
- painful periods
- painful sex
- pain during bowel movements
Symptoms unique to this condition include:
- discomfort during bowel movements
- bleeding from the rectum
- constipation or diarrhea
- pain in the rectum that can feel like you’re “seated on a thorn”
These symptoms will often worsen during your menstrual periods.
Doctors don’t know exactly what causes rectovaginal or other forms of endometriosis. But they have a few theories.
The most common theory of endometriosis is related to backward menstrual blood flow. This is known as retrograde menstruation. During menstrual periods, blood and tissue can flow backward through the fallopian tubes and into the pelvis, as well as out of the body. This process can deposit endometrial tissue in other parts of the pelvis and abdomen.
However, recent research found that while up to 90 percent of women can experience retrograde menstruation, the majority don’t go on to develop endometriosis. Instead, researchers believe the immune system has an important role in this process.
Other possible contributors to developing this condition likely include:
- Cell transformation. Cells affected by endometriosis respond differently to hormones and other chemical signals.
- Inflammation. Certain substances that have a role in inflammation are found in high levels in the tissues affected by endometriosis.
- Surgery. Having a cesarean delivery, hysterectomy, or other pelvic surgery may be a risk factor for ongoing episodes of endometriosis. A 2016 study in Reproductive Sciences suggests these surgeries may trigger the body to encourage growth of already active tissue.
- Genes. Endometriosis can run in families. If you have a mother or sister with the condition, there’s a two- to tenfold risk of developing it, rather than someone without a family history of the disease.
Women ages 21 to 25 are most likely to develop rectovaginal endometriosis.
Rectovaginal endometriosis can be difficult to diagnose. There are no clear guidelines on how to identify this form of the disease.
Your doctor will first ask questions about your symptoms, including:
- When did you first get your period? Was it painful?
- Do you have symptoms like pelvic pain, or pain during sex or bowel movements?
- What symptoms do you have around and during your period?
- How long have you had symptoms? Have they changed? If so, how have they changed?
- Have you had any surgery to your pelvic area, such as a cesarean delivery?
Then, your doctor will examine your vagina and rectum with a gloved finger to check for any pain, lumps, or abnormal tissue.
Your doctor may also use one or more of the following tests to look for endometrial tissue outside of the uterus:
- Ultrasound. This test uses high-frequency sound waves to create pictures of the inside of your body. A device called a transducer can be placed inside your vagina (transvaginal ultrasound) or rectum.
- MRI. This test uses powerful magnets and radio waves to create pictures of the inside of your abdomen. It can show areas of endometriosis in your organs and abdominal lining.
- CT colonography (virtual colonoscopy). This test uses low-dose X-rays to take pictures of the inner lining of your colon and rectum.
- Laparoscopy. This surgery is often the best way to confirm the diagnosis. While you’re asleep and pain-free under general anesthesia, your surgeon makes a few small cuts in your belly. They’ll place a thin tube with a camera on one end, called a laparoscope, into your belly to look for endometrial tissue. A sample of tissue is often removed for testing.
After your doctor identifies endometrial tissue, they’ll assess its severity. Endometriosis is divided into stages based on the amount of endometrial tissue you have outside your uterus and how deep it goes:
- Stage 1. Minimal. There are some isolated areas of endometrial tissue.
- Stage 2. Mild. The tissue is mostly on the surface of organs without scarring
- Stage 3. Moderate. More organs are involved, with some areas of scarring.
- Stage 4. Severe. There are multiple organs involved with extensive areas of endometrial tissue and scarring.
However, the stage of endometriosis has no relation to symptoms. There can be significant symptoms even with lower levels of disease. Rectovaginal endometriosis is often stage 4.
Because this condition is on-going and chronic, the goal of treatment is to control your symptoms. Your doctor will help you choose a treatment based on how severe the condition is and where it’s located. This usually involves a combination of surgery and medication.
Surgery to remove as much of the extra tissue as possible provides the greatest relief. Research suggests it may improve up to 70 percent of pain-related symptoms.
Endometriosis surgery can be done laparoscopically or robotically through small incisions using small instruments.
Surgical techniques can include:
- Shaving. Your surgeon will use a sharp instrument to remove the areas of endometriosis. This procedure can often leave some endometrial tissue behind.
- Resection. Your surgeon will remove the part of the intestine where endometriosis has grown, and then reconnect the bowel.
- Discoid excision. For smaller areas of endometriosis, your surgeon may cut out a disc of affected tissue in the intestine and then close the opening.
Currently, there are two main types of medications used to treat rectovaginal and other types of endometriosis: hormones and pain relievers.
Hormone therapy can helps slow the growth of endometrial tissue and decrease its activity outside of the uterus.
Types of hormone drugs include:
- birth control, including pills, patch, or ring
- gonadotropin-releasing hormone (GnRH) agonists
- danazol, less commonly used today
- progestin injections (Depo-Provera)
Surgery to treat rectovaginal endometriosis can cause complications such as:
- bleeding inside the belly
- a fistula, or abnormal connection, between the vagina and rectum or other organs
- chronic constipation
- leaking around the reconnected bowel
- trouble passing stools
- incomplete symptom control that requires more surgery
Women with this type of endometriosis can have more trouble getting pregnant. The pregnancy rate in women with rectovaginal endometriosis is lower than the rate in women with less severe forms of the disease. Surgery and in vitro fertilization can increase your odds of conception.
Your outlook depends on how severe your endometriosis is and how it’s treated. Having surgery can relieve pain and improve fertility.
Because endometriosis is a painful condition, it can have a big impact on your day-to-day life. To find support in your area, visit the Endometriosis Foundation of America or the Endometriosis Association.