A sonohysterogram is an imaging study of the uterus. Doctors insert fluid into the uterus via the cervix to examine the uterine lining. This approach allows a doctor to identify more structures than if ultrasound with no fluid was used.

This test is one example of imaging used to diagnose the cause of underlying pelvic pain, infertility, or vaginal bleeding.

A doctor will recommend a sonohysterogram when they need to examine the structure of your uterus and its lining. Test uses range from testing for infertility to diagnosing the cause of uterine bleeding.

A doctor may recommend a sonohysterogram for a variety of symptoms and conditions including:

  • determining if your fallopian tubes are blocked
  • examining the uterus if you’ve had miscarriages or have been unable to get pregnant
  • examining scar tissue, such as endometriosis
  • identifying abnormal growths, which could include uterine fibroids or polyps
  • identifying irregularities in the uterine lining
  • visualizing the uterus’ shape

An OB-GYN typically performs a sonohysterogram at their office.

Before undergoing a sonohysterogram, a doctor will have you take a pregnancy test. You shouldn’t have a sonohysterogram if you’re pregnant or experiencing an inflammatory pelvic disorder.

The sonohysterogram is usually scheduled when you’re not on your period or experiencing vaginal bleeding. Both can affect how well the doctor can see the uterine lining.

The test usually takes place one week after you start your period as this reduces infection risk. It’s also when the uterine lining is at its thinnest, which helps doctors identify abnormalities more easily.

You’ll be asked to empty your bladder before the test. You’ll lie down on an examination table or bed. Sometimes, a doctor will perform a pelvic exam first to check for pain or the possibility of infection.

There are three main parts of a sonohysterogram:

  1. Performing an initial transvaginal ultrasound. A transvaginal ultrasound involves inserting a special ultrasound probe into the vagina. The probe emits sound waves that recreate an image of the uterine lining. A doctor will usually take an initial scan without any fluid in the uterus. The images are projected on the ultrasound screen.
  2. Inserting fluid into the uterus. After the doctor examines the uterus with the ultrasound probe, they’ll insert a speculum in the vagina. (It’s not uncommon that you would be handed the speculum to insert.) This is a special tool designed to keep the vagina open, making it easier to reach the cervix on the way to the uterus. The doctor uses a special swab to clean the inside of the cervix and then inserts a tube that can send fluid to the cervical opening. The fluid will cause the uterus to enlarge slightly and also makes the uterine lining (known as the endometrium) easier to visualize.
  3. Performing the ultrasound. The doctor once again inserts the transvaginal ultrasound probe and uses the tube to send more fluid through the vagina and into the uterus. Sometimes, a woman may experience some cramping when this fluid goes through the uterus. The doctor will use the ultrasound to examine the uterine lining and sometimes note the flow of fluid from the uterus and into the fallopian tubes. Sometimes, they’ll use a special feature of the ultrasound, known as the Doppler ultrasound. This method allows the doctor to identify blood flow or blood flow blockages. The Doppler is useful in identifying blood clots as well as blood supplies to polyps and tumors.

The entire process usually takes about half an hour, according to the Radiological Society of North America.

You should be able to return to your usual activities almost immediately after undergoing a sonohysterogram. The procedure doesn’t usually cause serious side effects that would interfere with work or school. You may wish to abstain from intercourse for a day or so if you have any discomfort. Any light bleeding you experience should stop within a couple days.

You may experience some light bleeding or cramping following the procedure. This is because the tissues can become irritated from using the transvaginal ultrasound and from having fluid inserted in the uterus.

Most doctors advise taking anti-inflammatory drugs, such as ibuprofen or acetaminophen, to relieve discomfort.

Sometimes, a woman may experience a pelvic tissue infection after a sonohysterogram. Symptoms of this condition can include fever, pain, and unusual discharge from the vagina. You should call your ob-gyn if you have these symptoms after a sonohysterogram.

Because ultrasound uses sound waves instead of radiation, there is no radiation exposure during the test.

A sonohysterogram is an alternative or a complementary diagnostic method to a magnetic resonance imaging (MRI) scan, hysteroscopy, or hysterosalpingogram (HSG).

In contrast to the sonohysterogram, an HSG is a radiology test that does involve using X-rays. A doctor performs this procedure by injecting radioactive dye into the uterus. If the fallopian tubes are open, the contrast dye fills the tubes and shows up on an X-ray.

This test is often indicated if a doctor can’t identify if there is an abnormality of the fallopian tubes by looking at a sonohysterogram or if fertility issues are being investigated.

A sonohysterogram is a short, minimally invasive procedure that allows a doctor to visualize the uterine lining. Sometimes a doctor will recommend follow-up testing or treatments depending upon what they see during the ultrasound.

If you’ve been having trouble getting pregnant, and your doctor sees that your fallopian tubes are blocked, surgical repair or in vitro fertilization (IVF) might be options to discuss.