Endometriosis Ultrasound and Tests: What To Expect

Endometriosis occurs when tissue that lines the uterus (womb) grows elsewhere, usually on the ovaries, fallopian tubes, and the area behind your uterus. This tissue can also grow on the bladder, bowel, diaphragm, and the space between the lungs and chest wall.

Imaging techniques can give healthcare providers a look inside your body. For endometriosis, imaging can help providers make a diagnosis, prepare for surgery, and monitor the condition.

A transvaginal ultrasound is used to see inside your uterus and to look at your ovaries, fallopian tubes, and cervix. This is the first imaging tool used when a healthcare provider thinks you might have endometriosis because it is widely available and relatively low cost.

Why It’s Done: Transvaginal ultrasounds are done to help diagnose endometriosis. They work best to identify deep infiltrating endometriosis (DIE), a more advanced endometriosis stage. They can also find endometriomas (an endometriosis cyst) and pelvic adhesions (scar tissue that can form from endometriosis).

How It’s Done: You will lie on an exam table with your legs bent or placed in stirrups. The provider will insert the top portion of an ultrasound probe—which looks like a wand—inside your vagina. The probe uses sound waves to record waves from your body, which an ultrasound machine will create images based on. A radiologist will study the images to help understand what is happening inside your uterus and nearby organs.

Pros: Transvaginal ultrasounds are a much less invasive technique than surgeries. They can help diagnose certain types of endometriosis. They don’t require preparation. There are no harmful side effects, and you can return to your normal activities after the procedure.

Cons: Transvaginal ultrasounds may not be able to identify all forms of endometriosis, and they can’t officially diagnose endometriosis. Although there is usually no pain with a transvaginal ultrasound, some people find it uncomfortable to have a transducer placed inside them. This procedure can be triggering for people who have experienced sexual abuse.

Magnetic resonance imaging (MRI) is a procedure that uses magnetic fields and radio waves to create images of the inside of your body. MRI is considered the next best imaging tool for endometriosis.

Why It’s Done: MRIs are used primarily to get a larger view of the body rather than focusing in detail on specific organs and structures. In endometriosis care, MRIs are often used before surgery to help your surgery team prepare for the procedure. MRI can be done if ultrasound findings are not clear or if they think there’s endometriosis on the bowel, bladder, or ureters (tubes that carry urine from kidneys to bladder).

How It’s Done: An MRI machine is a tube-like machine. You will lie on your back and be asked not to move while inside the machine. Contrast material may be administered through an IV. The exam typically lasts 30-50 minutes. The MRI machine can make loud sounds; you may be given earplugs.

Pros: MRIs are less invasive than surgery for endometriosis. They are tolerable for most people. Unlike X-rays, MRIs don’t use radiation. Unless you were given medications to relax you during the procedure, you will be able to go back to your normal activities after your MRI is done.

Cons: MRIs can’t diagnose endometriosis, and they provide less detailed views of your organs than ultrasounds. While most people don’t mind MRIs, some find it hard to stay still or may experience claustrophobia (fear of enclosed spaces) while in the machine.

Laparoscopy itself is not an imaging technique. It’s a surgical procedure where small cuts are made in the abdomen so healthcare providers can see inside your body without making large cuts. Imaging performed during a laparoscopy provides an internal view.

Why It’s Done: Laparoscopy is the standard way to diagnose endometriosis officially. Your healthcare provider can look directly at your internal organs for signs of endometriosis and take biopsies (tissue samples) for testing. Biopsies are the only definitive way to diagnose endometriosis. With this procedure, providers can also tell how extensively your uterine tissue has grown on your other organs.

How It’s Done: You will be given medication that will put you to sleep. Once the surgery starts, a small cut is made near your belly button, and a tool called a laparoscope is inserted into the cut. A camera is attached to the laparoscope to see your pelvic organs. These images are sent to a video monitor so the surgeon can see inside during the surgery. After surgery, you will be moved to a recovery room to rest.

Pros: Laparoscopy is currently the only way to diagnose endometriosis officially. It’s also possible that some of the unwanted tissue can be removed during the surgery. Although laparoscopy is a surgery, it’s less invasive than other surgeries involving the stomach area.

Cons: Laparoscopy is a surgery that requires more time and recovery. Although complications aren’t common, they are possible and include damage to blood vessels or the development of a hernia (a bulge in the surgical area). Bleeding, infection, or damage to any organ in the abdomen and pelvis are also possible.

Transrectal ultrasounds are used to visualize areas near the rectum (the section between your colon and anus) and the back of the body. This imaging scan isn’t usually used in endometriosis diagnosis or care planning.

Why It’s Done: Transrectal ultrasounds are rarely used for endometriosis, but they may help when endometriosis is believed to be located in the area between the rectum and the uterus.

How It’s Done: Similar to a transvaginal ultrasound, a healthcare provider uses a transducer wand to see inside your body. For this imaging, the wand is placed in your anus. It doesn’t go very deep inside. You may feel pressure, like when you have to poop. You will lie on your side during the exam. It should be brief, 20 minutes or less.

Pros: Transrectal ultrasounds may be helpful if your other tests can’t find the source of your endometriosis and if you are experiencing symptoms primarily in your bowels or rectum.

Cons: Some people may find the procedure uncomfortable or embarrassing. This procedure can’t diagnose endometriosis.

Endometriosis can be difficult to diagnose, and it can sometimes take several years to get a proper diagnosis. Part of this is because many of the procedures used to help diagnose endometriosis can be costly and invasive, preventing or discouraging people from undergoing them.

Each case of endometriosis is different. Your healthcare provider will help you decide which imaging test is best based on your health history and symptoms. Remember, you have options that you should discuss with your provider. You should also ask about the benefits and risks of each procedure.

Transvaginal ultrasound and MRI are the primary imaging tools used when a healthcare provider suspects endometriosis.

Laparoscopy is a surgery that allows your provider to see inside your abdomen to look for endometriosis and take biopsies. It is the only way to diagnose endometriosis officially.

Your healthcare provider will help you determine the best tests and procedures for your endometriosis journey.