- Transvaginal ultrasounds involve a slender probe that's inserted into the vagina.
- The procedure can be uncomfortable but probably no worse than a pap smear.
- People who are pregnant or have a condition of the reproductive system may need one.
- Visit Insider's Health Reference library for more advice.
A transvaginal ultrasound is similar to an abdominal ultrasound in that they both use high-frequency sound waves to create images of internal organs.
The difference between them is that a transvaginal ultrasound requires a device to be inserted in the vagina to obtain these images while an abdominal ultrasound is done outside the body on the abdomen.
There are a few reasons someone may need a transvaginal ultrasound instead of an abdominal ultrasound, including in early pregnancy or to diagnose certain conditions, like ovarian cysts or uterine fibroids, says Kathleen Green, MD, an assistant professor in the department of obstetrics and gynecology at the University of Florida and an OB-GYN with Maven Clinic, a telehealth provider.
The procedure can be uncomfortable but is usually quick. Here's what you can expect.
What to expect
During a transvaginal ultrasound, a long, slender, wand-shaped probe connected to a computer is inserted about three to four inches inside the vagina, says Kecia Gaither, MD, an OB-GYN and director of perinatal services at NYC Health + Hospitals/Lincoln.
"The probe is inserted up to the cervix and it is generally not painful, but may be a little uncomfortable," Green says, adding that most patients tend to find it less uncomfortable than a typical pelvic exam or pap smear since the ultrasound probe is smaller than a speculum.
"The most important thing to do is to stay relaxed," Green says.
The exam is often done by a sonography technician, Green says. The technician will lubricate the probe to decrease discomfort and then gently insert it and move the probe around in a circular motion to capture images of pelvic organs including the:
- Cervix
- Uterus
- Ovaries
- Bladder
- Fallopian Tubes
- Endometrium
Like with a pelvic exam, you'll be asked to lie on your back with your feet in stirrups. The procedure takes about 15 to 30 minutes though this can vary depending on what kind of information the technician is trying to capture and which organs they are targeting, Gaither says.
For example, it may take more time to locate ovarian cysts or uterine fibroids than it would to confirm a pregnancy.
Images from the ultrasound are available in real-time, but will need to be interpreted by a physician or radiologist before you receive results, says Cheruba Prabakar, MD, an OB-GYN with Stanford Healthcare.
You may meet with a doctor right after the ultrasound to go over the results, or it may take a couple of days, depending on why the ultrasound was ordered and when a doctor or radiologist can review it, Prabakar says.
When you might need one
A transvaginal ultrasound bounces sound waves off internal organs to project images of what is going on inside your body. There are a few reasons why a doctor might order a transvaginal ultrasound including:
- In early pregnancy. Most pregnancies aren't visible with an abdominal ultrasound until about 8 to 10 weeks gestation, Green says. Before about 10 weeks, a transvaginal ultrasound is used to confirm a pregnancy that is too early to be seen with an abdominal ultrasound.
- Later in pregnancy. Because a transvaginal ultrasound is able to provide more detailed images than an abdominal ultrasound, it may also be used later in pregnancy to measure the cervix, evaluate patients for preterm labor, check the location of the placenta, or screen an early fetus for genetic conditions, Green says.
- As a diagnostic tool. If you are experiencing pelvic pain or abnormal bleeding, a doctor may order a transvaginal ultrasound as one of the first steps toward diagnosing certain conditions, like:
- Ovarian cysts
- Uterine fibroids
- Polyps
- Endometriosis
- Tumors of the bladder or cervix
- Ectopic pregnancy
- After an abnormal pelvic exam. If your provider notices something unusual during your annual pelvic exam, they may order a transvaginal ultrasound to get a better look at your pelvic organs, Gaither says. Outside of pregnancy, the uterus is usually too small for an abdominal ultrasound to properly examine, Green says, so a transvaginal ultrasound is often the best way to search for abnormalities of pelvic organs.
Insider's takeaway
A doctor may order a transvaginal ultrasound as a first step toward diagnosing conditions like ovarian cysts or uterine fibroids or to confirm an early pregnancy.
The procedure is typically done by a sonography technician who inserts an ultrasound probe about three to four inches inside the vagina.
The exam can be uncomfortable but usually only lasts about 15 to 30 minutes. A doctor or radiologist will review the images and discuss results with you either right away or within a couple of days of the ultrasound.