Pelvic ultrasonography (US) can be done with or without infusing the uterus and tubes with water or a substance that shows up on US.
The advantage of the US is that is gives information about soft tissues like the uterus and ovaries that an X-ray does not provide. Further, US evaluates the entire organ and not just the surface as seen by laparoscopy. Thus, the US can detect fibroids, adenomyosis, and ovarian structures such as cysts or the antral follicle count.
Water or a fluid which reflects on the US can be infused, similar to the hysterosalpingogram (HSG). This is highly accurate in determining structures within the uterine cavity such as polyps and fibroids. It can also detect scarring which cannot be seen if the water is not infused.
Finally, water infused sonography (SIS for saline infused sonogram) can determine if the fallopian tubes are open. The SIS is as accurate as the HSG but give considerably more information than the HSG. Furthermore, it can be done in a physician’s office and is less painful the HSG. There does remain the potential risk of infection.