Do Saline Infusion Sonograms Increase Fertility?

If you’re trying to get pregnant, you may be looking for ways to boost your fertility. On your quest, you might’ve come across the theory that a procedure called a saline infusion sonogram (SIS) can increase your odds of conceiving.

Read on to learn what SIS does and why some people believe it improves fertility.

Also known as a sonohysterogram, a saline infusion sonogram (SIS) is a type of transvaginal ultrasound that lets your doctor take a detailed look inside your uterus. 1

SIS is used to diagnose various uterine-related conditions, including: 2

• Uterine fibroids or polyps (typically non-cancerous growths) 3 4
• Intrauterine scarring (growth of scar tissue) 5
• An abnormally shaped uterus
• Uterine cancer

These conditions are all potential factors that can contribute to infertility, which is why doctors may recommend you get an SIS if you’re struggling to get pregnant.

How do doctors perform SIS?

SIS is a relatively quick procedure that typically takes less than 30 minutes. It doesn’t involve radiation (in contrast to an X-ray), and you’ll be awake throughout it.

You’ll have to empty your bladder before the procedure starts. 2

Here’s how the procedure usually goes: 2

1. You’ll undress from the waist down and lie on an exam table
2. The doctor will gently insert an ultrasound wand (transducer) into your vagina to capture a set of initial images
3. They’ll then insert a medical tool (a speculum) into your vagina to keep it open and clean your cervix with a swab
4. Next, they’ll insert a thin, flexible tube (a catheter) into your cervix to reach your uterus, then they’ll remove the speculum
5. They’ll reinsert the transducer into your vagina and send a sterile saline solution through the catheter to fill your uterus
6. Once it’s filled with enough saline, your doctor will capture detailed images of the inside of your uterus to look for any abnormalities before removing the transducer and catheter

While there does seem to be a correlation between SIS and improved fertility (more on this below), it’s unclear whether the procedure directly improves your chances of getting pregnant.

SIS is meant to be a diagnostic tool that can help doctors identify the root causes of infertility—not a type of fertility treatment itself.

For instance, your doctor might use SIS to diagnose a fertility-related illness. After doing so, they can treat the medical condition, which may, in turn, improve your fertility.

Why do many people claim it’s easier to conceive after undergoing SIS?

Many women report conceiving shortly after undergoing SIS, and there are studies that support these claims. These include a 2023 study that suggests SIS increases the rate of spontaneous pregnancy, particularly within the first 30 days after SIS and in women who faced infertility for shorter durations.

Experts think this might be because when your doctor fills your uterus with saline solution during the procedure, they may inadvertently do one or more of the following:

• “Flush out” minor blockages in your fallopian tubes (e.g., bacteria, mucus, etc.)
• Improve blood flow in your uterine lining
• Induce ovulation

Keep in mind that these are only guesses and not definite facts; they still need more research, and the general consensus is that any improvement in your fertility that you’ll see from SIS will be slight. You shouldn’t undergo it expecting it to increase your fertility.

After the procedure, you might experience: 6

• Cramping
• Light spotting
• Watery discharge (which is saline fluid, not anything you need to worry about)

In most cases, you can go home and carry on with your day right after an SIS.

SIS is a generally safe procedure with few risks. However, in very rare cases, you might get a pelvic infection, which has symptoms including: 2 7

• A fever
• Pelvic, lower belly, or lower back pain
• Vaginal discharge with unusual smell, color, or texture

Again, you’ll most likely have no issues with the procedure, but if you notice any signs of infection, call your doctor right away.

The main purpose of SIS isn’t to treat infertility but to diagnose uterine issues. Of course, it’s a welcome surprise if you get pregnant after SIS, but keep your expectations modest—there isn’t sufficient evidence at the moment to prove that SIS improves fertility.