What to Know When Your OB-GYN Recommends Saline Infusion Sonography
What does it mean when your doctor orders a SIS, or saline-infusion sonography? Our experts explain.
If you’ve ever experienced irregular, heavy or post-menopausal bleeding, struggle with infertility or had an ultrasound and something came up abnormal, or the cavity was not clearly seen, your doctor could order a saline infusion sonography (SIS). This special ultrasound gives your doctor a better look at your uterus, especially the cavity.
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What exactly is a SIS and what does it involve? Gynecologist Oluwatosin Goje, MD, explains all the nuances that come with getting a SIS.
The procedure itself goes quickly and usually doesn’t hurt, says Dr. Goje.
A SIS is similar to the transvaginal ultrasound that’s often performed, but with one added step: Sterile fluid is used to gently expand and hold the walls of your uterus apart. This helps your doctor get a better view of the uterine cavity and any irregularities can be seen more clearly. It can also show whether there are any polyps, or abnormal tissue growths, extending inside the uterus, any fibroids pressing on the lining and whether the uterine cavity is normally shaped.
Your doctor will order a SIS for you if you:
“A SIS is a very safe procedure and complications from the procedure are rare,” says Dr. Goje. “You may feel a slight discomfort when the fluid is gently introduced into the uterine cavity. The most common complication is pelvic infection, but this is rare.”
There isn’t much you have to do to prepare for a SIS. To avoid accidentally doing the procedure in early pregnancy, Dr. Goje recommends getting it done after your period ends but before you ovulate.
“A SIS is performed between day 6 to 11, considering the first day of menstrual bleeding as day 1,” says Dr. Goje.
If you’re pregnant, your doctor won’t schedule a SIS for you.
Your doctor may suggest you take acetaminophen or ibuprofen (Advil®, Motrin®) before the procedure. But if you prefer a different medication or have allergic reactions to the listed medications, talk to them about your options.
A SIS will be able to help you be on your way toward the best treatment for you. Talk to your doctor to figure out if scheduling a SIS is your best option.