Many people undergo an HSG test (hysterosalpingogram) as part of their fertility workup to check for blocked fallopian tubes or abnormalities in the uterus. But what you might not expect is that some doctors mention a surprising side effect: It may actually increase your chances of getting pregnant in the months right after the procedure.

This claim has shown up in YouTube videos, patient forums, and even in a few research journals. But is there any truth to it?

In this post, we will break down the connection between HSG and fertility, explain what is medically proven (and what is not), and help you understand what to expect after your HSG.

What the HSG Test Actually Does

An HSG test uses contrast dye and X-ray imaging to evaluate whether your fallopian tubes are open and whether your uterus has a healthy shape. It is typically done between Day 6–12 of your cycle, just after your period ends but before ovulation.

During the test, dye is inserted through the cervix and watched on a screen as it moves through the uterus and into the fallopian tubes. If the dye flows freely out both tubes, they are considered open. If not, it may indicate blockage or spasm.

The main goal of the HSG is diagnostic. But there is a potential added benefit.

Learn more: How to Prepare for an HSG Test

Can an HSG Test Actually Increase Fertility?

Research shows that, in some cases, an HSG may temporarily boost fertility. This phenomenon is often called the “tubal flushing effect.”

The idea: if a small amount of debris, mucus, or inflammation is partially blocking the tubes, the injection of dye may help clear them out, potentially making it easier for the egg and sperm to meet in the next few cycles.

One of the most cited studies on this topic is the H2Oil trial, originally published in 2017 in The New England Journal of Medicine (NEJM), which found that women who underwent an oil-based HSG had significantly higher pregnancy rates within 6 months compared to those who received a water-based dye.

Key findings from the H2Oil study:

  • This was a large, randomized trial involving 1,119 women with unexplained infertility.
  • Each participant underwent an HSG procedure using either oil-based or water-based contrast, assigned at random.
  • Women in the oil-based contrast group had a 40% pregnancy rate within 6 months.
  • Women in the water-based group had a 29% pregnancy rate.

The study concluded that oil-based contrast led to significantly higher rates of ongoing pregnancy and live births. However, it is important to note that not all clinics use oil-based contrast, and other factors – such as age, sperm quality, and ovulation patterns – also play a role in fertility outcomes.

So, Does an HSG Test Increase Fertility?

Here is the bottom line:

  • In some patients, fertility may improve slightly in the first 1–3 months after an HSG procedure, especially if there were minor tubal blockages.
  • The effect is more pronounced with oil-based dye, but this is less commonly used in U.S. fertility clinics due to safety considerations and provider preference.
  • If your tubes are already open, the HSG does not “boost” fertility in any lasting way.
  • If your HSG showed blocked tubes, pregnancy may still be possible with proper treatment, but the flushing effect is unlikely to help alone.

Is There a Fertility Boost After HSG?

Some research suggests that if an HSG test improves fertility, the effect is most likely to occur within the first 3 months after the procedure – a window sometimes referred to as the tubal flushing effect. This benefit appears more pronounced with oil-based contrast, though water-based HSGs, which are more commonly used in the U.S., may still offer a fertility boost for some patients. The effect is temporary and varies by individual, but it may offer a meaningful opportunity to conceive during this time.

If your fallopian tubes are open and no major issues were found, the months following an HSG may be an ideal time to try conceiving – either naturally or with treatment such as IUI – depending on your personal fertility profile. Factors like sperm health, ovulation patterns, and your complete diagnostic picture all play a role.

In cases where the HSG reveals more serious issues, surgical treatment or IVF may be recommended. Contact our fertility specialists to discuss your options and next steps.

FAQs: HSG and Fertility

Does an HSG test help you get pregnant?

In some cases, yes, especially if the test clears minor debris or mucus that may have been partially blocking the fallopian tubes. This is known as the tubal flushing effect. However, the benefit is not guaranteed, and the test is primarily used for diagnosis rather than treatment.

Studies suggest that oil-based contrast may result in slightly higher pregnancy rates in the months after the test. However, water-based contrast is more commonly used in U.S. clinics and is still highly effective for evaluating the uterus and fallopian tubes.

In most cases, you can begin trying immediately, as long as no complications occurred during the procedure. Many patients try to conceive in the same cycle or shortly afterward, particularly if the HSG results were normal.

Not exactly. The test may help flush out minor obstructions, but it cannot repair structural damage, scarring, or complete blockages. If your tubes are severely affected, our fertility specialists can recommend further testing or assisted reproductive options.

If a fertility benefit occurs, it typically happens within the first 1-3 months following the procedure. After that, the effect tends to diminish, and additional fertility support may be needed depending on your overall situation.

Why New Hope?

The HSG test is a critical diagnostic tool and, for some patients, it may also act as a temporary fertility boost. If your results were normal, the next few months may be the best time to try conceiving naturally or with the help of fertility treatments like IUI.

If your results showed a blockage or abnormality, or if you are unsure what to do next, speaking with a fertility doctor is the best next step. Our team can review your HSG findings, explain your options, and guide you toward the right treatment plan, whether that’s Timed Intercourse, IUI, or IVF.

Ready to learn more? Call us at (347) 970-8479 or schedule your initial consultation now.

New Hope Editorial Team

Written by the New Hope Editorial Team

As experts in IVF and Assisted Reproductive Technologies, we are committed to educating and empowering people on their fertility journey with accurate information and compassionate care.