Pre-IVF Evaluation in the U.S.: Why Is Saline Infusion Sonography So Common?

In most fertility centers across the United States, a Saline Infusion Sonography (SIS) is considered a standard part of the pre-IVF workup.

The concept is simple: A small amount of sterile saline is infused into the uterine cavity to gently separate the uterine walls, allowing ultrasound to obtain a clearer view.

This helps doctors better evaluate:

• Endometrial thickness and contour

• Possible polyps

• Submucosal fibroids

• Endometrial cysts

• Congenital or acquired cavity abnormalities

If the SIS reveals suspected polyps or any abnormality, physicians often recommend a follow-up procedure — hysteroscopy.

---

1. What Exactly Is a Hysteroscopy? Does It Hurt?

A hysteroscopy involves passing a thin, lighted scope through the cervix into the uterine cavity. Think of it as a “high-definition camera” that allows direct visualization of the inside of the uterus.

Its benefits are significant:

① More Accurate Diagnosis

Direct visualization is far clearer than ultrasound. It allows doctors to detect:

• Small polyps

• Hidden uterine septum

• Intrauterine adhesions

• Irregular endometrium

• Small fibroids

Many of these cannot be reliably seen on standard ultrasound.

② Diagnosis and Treatment in the Same Procedure

This is one of hysteroscopy’s biggest advantages.

If polyps, adhesions, or small fibroids are found, they can often be removed during the same session —diagnosis and treatment in one procedure.

③ Particularly Valuable After Repeated Implantation Failure

For patients with multiple failed embryo transfers, hysteroscopy often uncovers issues such as:

• Fine adhesions

• Focal endometritis

• Tiny polyps

• Subtle uterine septum

Even small abnormalities may interfere with implantation and are frequently missed by routine imaging.

2. Who Should Consider Hysteroscopy?

It is not required for every patient, but is strongly recommended for:

✔ Abnormal findings on saline infusion sonography— This is the clearest indication.

✔ Unexplained repeated implantation failure. Hysteroscopy helps rule out hidden uterine issues.

✔ Ultrasound showing irregular or heterogeneous endometrium

✔ A history of miscarriage, D&C procedures, or uterine surgery. Higher risk of adhesions.

✔ Symptoms such as decreased menstrual flow or worsening cramps. May suggest intrauterine pathology.

3. If My SIS Is Completely Normal, Do I Still Need Hysteroscopy?

In the U.S., hysteroscopy is not mandatory when SIS is normal.

Most American fertility specialists agree:

• SIS provides excellent visualization

• No symptoms + no history of failed transfers

• No prior uterine surgery

➡️ A routine hysteroscopy is usually unnecessary.

However, if a patient wants absolute reassurance, most physicians are willing to schedule it.

4. Will Hysteroscopy Delay My IVF Cycle?

Generally, no.

As long as recovery is smooth, the transfer cycle can typically be started within one month. If a simple polypectomy is performed with no infection, recovery is even faster.

5. Summary: Hysteroscopy Isn’t for Everyone, but It’s Crucial for the Right Patients

In simple terms:

SIS = Screening

Hysteroscopy = Diagnosis + Treatment + Repair

If you are:

• Doing your first transfer

• Normal SIS

• No symptoms

• No miscarriage or surgical history

➡️ You can usually skip hysteroscopy.

But if you have:

• Polyps seen on SIS

• Prior D&C or uterine surgery

• Implantation difficulties or repeated failures

• Concerns about the uterine environment

➡️ Hysteroscopy is highly worthwhile.

A clean, smooth, polyp-free uterine cavity is one of the most important foundations for successful embryo implantation.