Pelvic ultrasound

What Is Pelvic Ultrasound Imaging?

Pelvic ultrasound (sonography) sends sound waves into the body and records their reflections off internal organs to build an image. This technique involves no ionizing radiation (x-ray).

In women, doctors most often use it to examine the uterus and ovaries, and during pregnancy to monitor the embryo or fetus. In men, it usually focuses on the bladder and prostate gland. Because the images are captured in real time, the scan can also show movement — such as blood flow in arteries and veins.

Common Uses

For women, ultrasound can help find the cause of pelvic pain, abnormal bleeding, or other menstrual problems. It can also identify masses such as ovarian cysts, uterine fibroids, or ovarian and uterine cancers.

For men, it’s a valuable tool for evaluating the prostate gland and seminal vesicles.

For both men and women, a pelvic ultrasound can help identify stones, tumors, and other disorders in the urinary bladder.

How Should I Prepare?

Wear comfortable, loose-fitting clothing. For a transabdominal scan, drink up to six glasses of water two hours before your exam so your bladder is full — this helps us visualize the uterus, ovaries, and bladder wall. A transvaginal exam needs no bladder filling.

How Does the Procedure Work?

Ultrasound works on the same principle as the sonar that bats, ships, and fish-finders use. A controlled sound wave bounces off objects, and the reflected waves reveal distance, size, shape, and internal consistency (fluid, solid, or mixed).

The transducer acts as both a loudspeaker and a microphone. When the technologist presses it against your skin, it sends inaudible, high-frequency sound waves into the body. As these waves bounce back off your fluids and tissue, the transducer records the strength and character of the echoes. With Doppler ultrasound, it also captures tiny shifts in the sound wave’s pitch and direction.

A computer measures these signals instantly and builds a real-time picture on the monitor. The technologist can freeze individual frames to capture still images, which we use for measurements and to document key positions during the exam.

Doppler ultrasonography specifically detects moving blood cells in vessels. It measures their direction and speed using the Doppler effect, which evaluates movement from the frequency shift in the reflected echoes.

What Will I Experience?

Pelvic ultrasound should be painless. For a transabdominal scan, you’ll lie on your back while the technologist applies gel and presses the transducer against your skin, moving it until they capture the needed images. You may feel some pressure, especially if your exam requires a full bladder.

Doctors often use a transvaginal ultrasound to look for a cause of pelvic pain, but the scan itself shouldn’t be painful — it’s usually more comfortable than a manual gynecologic exam.

A transrectal ultrasound of the prostate feels similar to a rectal exam your doctor performs in the office.

Almost all pelvic ultrasound exams take less than 30 minutes.

Benefits vs. Risks

Benefits

• Non-invasive (no needles or injections in most cases) and usually painless.
• Widely available and easy to use.
• Uses no ionizing radiation — the preferred imaging method for pregnant women and their unborn babies.
• Can identify and evaluate a range of urinary and reproductive system disorders in both sexes, without any x-ray exposure.
• Shows structure, movement, and function in organs, blood vessels, and the growing fetus.

Risks

Standard diagnostic ultrasound has no known harmful effects on humans.

What Does the Equipment Look Like?

The equipment is a transducer and a monitor. The transducer is a small, hand-held device that resembles a microphone. For an abdominal scan, the technologist spreads lubricating gel on the lower abdomen and presses the transducer against the skin. For a transvaginal scan, the technologist inserts a covered, lubricated, wand-like device into the vaginal canal.

The image appears immediately on a nearby screen. The technologist watches this screen throughout the exam and captures representative images — and you can often see the screen too.

How Is the Procedure Performed?

There are three approaches: transabdominal, transvaginal (in women), and transrectal (in men). All rely on the same high-frequency sound principles.

Transabdominal: with a full bladder, you lie on the exam table while the technologist applies gel to your lower abdomen. This helps the transducer make good contact with the skin, since sound waves can’t pass through air. The technologist presses the transducer against the skin and sweeps it to image the pelvic organs, and can perform Doppler imaging through the same transducer.

Transvaginal: performed much like a gynecologic exam, after you empty your bladder. The transducer tip is smaller than a standard Pap-test speculum. The technologist places a protective, lubricated cover over it, then inserts it about two to three inches into the vagina. They take images from different angles to get the best views of the uterus and ovaries, and can perform Doppler imaging the same way. You’ll typically lie on your back with your feet in stirrups, as in a gynecologic exam.

Transrectal: since the prostate sits directly in front of the rectum, the technologist places a protective, lubricated cover over the transducer, then inserts it into the rectum — keeping the distance the sound has to travel short. They take images from different angles for the best view of the prostate. You’ll typically lie on your left side with your knees bent slightly toward your chest.

Each approach has its advantages. Transabdominal imaging gives a wider view of the whole pelvis and how internal structures relate to one another. Since the transducer sits closer to the area under examination, transvaginal and transrectal approaches can offer better detail — helpful for locating an early embryonic heartbeat, evaluating uterine texture, or measuring an ovarian cyst. Your physician or radiologist will decide which approach, or combination, is right for you.

When the exam is complete, you may need to dress and wait while we review the images. Often, though, the sonographer or radiologist reviews them in real time as they capture them, and you can leave right away.

Who Interprets the Results, and How Do I Get Them?

A radiologist — a physician experienced in ultrasound and other radiology exams — reviews the images and sends a signed report to your personal physician. You’ll receive your results from the clinician or referring physician who ordered the test.

What Are the Limitations of Pelvic Ultrasound?

Air or gas reflects ultrasound waves, so ultrasound isn’t an ideal imaging exam for the bowel. Doctors may prefer barium exams or CT scanning for bowel-related problems.

Ultrasound also has difficulty penetrating bone, so it can only show the outer surface of bony structures, not what lies within or beyond them. For imaging bone or the internal structure of certain joints, other methods such as MRI may work better.

Ready to book your pelvic ultrasound? Visit our Ultrasound service page for booking details, or book an appointment directly.