Hysterosalpingogram (HSG)

What is a hysterosalpingogram (HSG)?

A hysterosalpingogram (HSG) is an imaging procedure that diagnoses certain causes of female infertility. It involves your healthcare provider inserting contrast dye into your uterus and fallopian tubes. Then, they use a series of X-rays (fluoroscopy) to take pictures of the structure of your uterine cavity and fallopian tubes.

An HSG can help your provider spot issues in your reproductive anatomy that may prevent you from getting pregnant. These issues include blocked fallopian tubes and an irregularly shaped uterus. Your provider may recommend an HSG alongside other tests that check for causes of infertility, like a pelvic ultrasound, hysteroscopy or MRI.

In some cases, providers may recommend getting an HSG a few months after a tubal ligation. This is to make sure your fallopian tubes are completely blocked.

How does an HSG test work?

During an HSG, a dye fills your uterine cavity and fallopian tubes. The dye creates an outline of your uterus and fallopian tubes that stands out on an X-ray.

If the series of X-rays shows the dye flowing through your fallopian tubes, they’re open. The dye should spill out through your fimbriae (the ends of your fallopian tubes). (Your body will absorb it without any issues.) If the dye meets a barrier that prevents the flow, your fallopian tubes are blocked.

How do I prepare for an HSG test?

Ideally, you’ll schedule the HSG seven to 10 days after the first day of your menstrual period. This timeframe is typically before ovulation, which minimizes the chance that you could be pregnant during the test.

Before the test, tell your healthcare provider if you:

• Are allergic to iodine or contrast dye
• Have a pelvic infection or any signs of a sexually transmitted infection (STI)
• Have current heavy vaginal bleeding
• Might be pregnant

Follow your provider’s instructions to prepare for your procedure. Your provider may recommend that you take:

• Over-the-counter medicine for pain an hour before your procedure
• Antibiotics beforehand to prevent infection

Arrange for someone to drive you home after the test. You may feel up to driving yourself, or you may experience cramping that makes driving difficult. It’s a good idea to have someone to assist, just in case.

What should I expect during the HSG procedure?

In general, you can expect the following during a hysterosalpingogram:

1. You’ll lie on a table, with your knees bent and legs open, as if you were having a pelvic exam. The machine taking the X-rays (fluoroscopy machine) will be above the table.
2. Your provider will insert a speculum into your vagina that will widen it, allowing your provider to access your cervix.
3. Your provider will clean your cervix and insert a small catheter in it for the dye to travel through.
4. Your provider will remove the speculum. They’ll ask you to straighten your legs flat on the table.
5. Your provider will slowly pump the dye solution into your uterus while the radiologic technologist operates the fluoroscopy machine. You may feel cramping at this point.
6. Your provider may ask you to change positions to assess how the dye moves through your fallopian tubes.
7. After they get enough X-ray pictures, your provider will remove the catheter without reinserting the speculum.

An HSG usually takes less than five minutes. You can go home on the same day of your procedure.

Is it painful?

Mild pain or discomfort is common with an HSG — both during the procedure and afterward. You may feel cramping when your healthcare provider inserts the dye solution into your uterus. You may experience more cramping if your tubes are blocked.

The cramping may last anywhere from five minutes after your procedure to a few hours. It may feel mild or moderate. Taking over-the-counter NSAIDs may help.

What are the risks?

Overall, an HSG is a safe test. It uses radiation to record X-ray pictures. But the amount of radiation is minimal.

Rare complications may include:

• Infection
• Injury to your uterus or cervix
• An allergic reaction to the dye solution

What can I expect after the test?

After the HSG, you may need to wear a pad to catch the extra dye solution as it leaks from your vagina. Often, the discharge is sticky and contains small amounts of blood.

You may also notice side effects, like:

• Cramps
• Dizziness
• An upset stomach or nausea
• A small amount of vaginal bleeding for a day or two

Depending on your comfort, you may go back to your everyday activities immediately after your HSG.

What does an HSG test show?

A hysterosalpingogram mainly finds if a fallopian tube blockage or an irregularly shaped uterus may be the cause of infertility.

Conditions that can cause fallopian tube blockage or damage include:

• Adhesions (Asherman’s syndrome)
• Endometriosis
• Prior ectopic pregnancy
• Sexually transmitted infections
• Tubal spasms

Irregular uterine shapes that an HSG may detect include:

• Arcuate uterus
• Bicornuate uterus
• Septate uterus
• Unicornuate uterus
• Uterine agenesis (missing or underdeveloped uterus)
• Uterus didelphys

An HSG may also find other uterine conditions, including:

• Adhesions
• Fibroids
• Polyps
• Uterine cancer (tumor)

If your results are abnormal, your healthcare provider will recommend additional testing and/or treatment options. Don’t hesitate to ask questions.

When should I call my doctor?

Call your healthcare provider if you have any of these symptoms after the HSG:

• Fainting
• Fever or chills
• Foul-smelling vaginal discharge
• Heavy vaginal bleeding
• Severe abdominal pain or cramping
• Vomiting

Can an HSG test clear blocked tubes?

The dye solution can potentially clear minor blockages and increase your chance of becoming pregnant. Researchers need more studies to prove this theory.

Does it increase the chance of pregnancy?

“Tubal flushing” refers to the process of injecting dye into your uterus and fallopian tubes, as with an HSG, but without doing an X-ray. Some studies suggest that tubal flushing improves fertility, especially during the first three to six months following the dye injection.

Still, these studies are of varying quality. Healthcare providers need more research before they can consider HSG to be a fertility treatment as well as a diagnostic procedure.

Can I get pregnant immediately after an HSG?

Generally, it’s safe to try to become pregnant within a few days following an HSG. Ask your healthcare provider to be sure.