What Is an Endovaginal Ultrasound?

An ultrasound scan is a medical imaging test in which sound waves are sent out from a probe and bounced back. The reflected sound waves are used to create a picture of the scanned area, which is then displayed as a black and white image on a screen. An endovaginal ultrasound, sometimes known as a transvaginal ultrasound, involves a probe being inserted into the vagina. In comparison to an abdominal ultrasound, which involves a probe being moved over the skin of the abdomen, an endovaginal ultrasound provides a more detailed picture of the pelvic organs, in particular the womb and ovaries.

Although many types of ultrasounds are carried out from outside the body, it is sometimes necessary for the ultrasound probe to be positioned inside the body, and an endovaginal ultrasound scan is one example. Internal ultrasound scans commonly are used to view the prostate gland, stomach, gall bladder and esophagus. While these types of medical tests may be uncomfortable, they are not usually painful.

Before the endovaginal ultrasound procedure, the patient may be asked to empty her bladder and to put on a hospital gown. The position required for the scan is similar to that of a pelvic exam or smear test, lying down with knees bent and the legs drawn apart. A slim probe, covered with a clean sheath and a layer of gel, is introduced into the vagina and images are taken from various angles. This technique provides an in-depth view of the walls and lining of the womb, and the cavity inside it, together with the ovaries.

Endovaginal ultrasounds are used to investigate symptoms such as pelvic pain, lumps in the pelvis, abnormal vaginal bleeding and problems during pregnancy. Conditions which may be seen more clearly with an endovaginal ultrasound include growths inside the womb, such as fibroids and polyps. The extra information obtained from an endovaginal scan can help in the diagnosis of ovarian cysts and cancers of the womb or ovaries. In an emergency, an endovaginal ultrasound may be preferable to an abdominal ultrasound because the patient is not required to have a full bladder.

One disadvantage of an endovaginal ultrasound is that the patient may experience more discomfort and the procedure may be a bit more embarrassing than an abdominal scan. Additionally, abdominal ultrasounds have a greater field of view, enabling cysts and growths to be viewed in the upper part of the pelvis, which could be out of range of an endovaginal scan. Sometimes more than one type of scan may be necessary in order to fully evaluate a condition. Typically, scans do not take very long and no harmful effects are known.