Transvaginal ultrasound

How the Test is Performed

You will lie down on a table with your knees bent and feet in holders called stirrups. The health care provider will place a probe, called a transducer, into the vagina. The probe is covered with a condom and a gel. The probe sends out sound waves, which reflect off body structures. A computer receives these waves and uses them to create a picture. The doctor can immediately see the picture on a nearby TV monitor.

The health care provider will move the probe within the area to see the pelvic organs. This test can be used during pregnancy.

In some cases, a special transvaginal ultrasound method called saline infusion sonography (SIS), also called sonohysterography or hysterosonography, may be needed to more clearly view the uterus.

This test requires saline (sterile salt water) to be placed into the uterus before the ultrasound. The saline helps outline any abnormal masses, so the doctor can get a better idea of their size.

SIS is not done on pregnant women.

How to Prepare for the Test

You will be asked to undress, usually from the waist down. A transvaginal ultrasound is done with your bladder empty or partially filled.

How the Test Will Feel

The test is usually painless, although some women may have mild discomfort from the pressure of the probe. Only a small part of the probe is placed into the vagina.

Why the Test is Performed

Transvaginal ultrasound may be done for the following problems:

• Abnormal findings on a physical exam, such as cysts, fibroid tumors, or other growths
• Abnormal vaginal bleeding and menstrual problems
• Certain types of infertility
• Ectopic pregnancy
• Pelvic pain

Transvaginal ultrasound is also used during pregnancy to:

• Evaluate cases of threatened miscarriage
• Listen to the unborn baby's heartbeat
• Look at the placenta
• Look for the cause of bleeding
• Monitor the growth of the embryo or fetus early in the prgnancy
• See if the cervix is changing or opening up when labor is starting early

Normal Results

The pelvic structures or fetus are normal.

Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

What Abnormal Results Mean

An abnormal result may be due to many conditions. Some problems that may be seen include:

• Birth defects
• Cancers of the uterus, ovaries, vagina, and other pelvic structures
• Infection, including pelvic inflammatory disease
• Nocancerous growths of the uterus and ovaries (such as cysts or fibroids)
• Twisting of the ovaries

Some problems or conditions that may be found specifically in pregnant women include:

• Ectopic pregnancy
• More than one fetus (twins, triplets, etc.)
• Miscarriage
• Placenta previa
• Placental abruption
• Problems with the baby's growth or the fluid level around the baby
• Shortened cervix, which increases the risk for preterm delivery or late miscarriage
• Structural problems in the baby
• Tumors of pregnancy, including gestational trophoblastic disease

Risks

There are no known harmful effects of transvaginal ultrasound on humans.

Unlike traditional x-rays, there is no radiation exposure with this test.

Alternative Names

Endovaginal ultrasound; Ultrasound - transvaginal; Sonohysterography; Hysterosonography; Saline infusion sonography; SIS

References

Katz VL. Diagnostic procedures: Imaging, edometrial sampling, endoscopy: Indication and contraindications, complications. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM eds. Comprehensive Gynecology. 5th ed. Philadelphia, Pa : Mosby Elsevier; 2007: chap 11.

Bradley L. Menstrual dysfunction. Women's health. In: Carey WD, ed. Cleveland Clinic: Current Clinical Medicine 2010. 2nd ed. Philadelphia, Pa: Saunders Elsevier;2010:section 14.

Lobo RA. Infertility: etiology, diagnostic evaluation, management, prognosis. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM, eds. Comprehensive Gynecology. 5th ed. Philadelphia, Pa: Mosby Elsevier;2007:chap 41.

Update Date: 9/11/2010

Updated by: Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, WA; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.