A pelvic ultrasound uses sound waves to make a picture of the organs and structures in the lower belly (pelvis).

A pelvic ultrasound looks at:

• The bladder, ovaries, uterus, cervix, and fallopian tubes of a woman. See a picture of female organs seen on pelvic ultrasound.
• The bladder, prostate gland, and seminal vesicles of a man. See a picture of male organs seen on pelvic ultrasound.

Organs and structures that are solid and uniform (such as the uterus, ovaries, or prostate gland) or that are fluid-filled (such as the bladder) show up clearly on a pelvic ultrasound. Bones or air-filled organs, such as the intestines, do not show up well on an ultrasound and may keep other organs from being seen clearly.

Pelvic ultrasound can be done three ways: transabdominal, transrectal, and transvaginal.

• Transabdominal ultrasound. A small handheld device called a transducer is passed back and forth over the lower belly. A transabdominal ultrasound is commonly done in women to look for large uterine fibroids or other problems.
• Transrectal ultrasound. The transducer is shaped to fit into the rectum. A transrectal ultrasound is the most common test to look at the male pelvic organs, such as the prostate and seminal vesicles. Sometimes, a small sample of tissue (biopsy) may be taken with small tools inserted through the rectum during a transrectal ultrasound.
• Transvaginal ultrasound. The transducer is shaped to fit into a woman's vagina. A woman may have both transabdominal and transvaginal ultrasounds to look at the whole pelvic area. A transvaginal ultrasound is done to look for problems with fertility. In rare cases, a hysterosonogram is done to look at the inside of the uterus by filling the uterus with fluid during a transvaginal ultrasound. Sometimes, a small sample of tissue ( biopsy) may be taken with small tools inserted through the vagina during a transvaginal ultrasound. See ultrasound images of ovarian cysts.

In all three types of pelvic ultrasound, the transducer sends the reflected sound waves to a computer, which makes them into a picture that is shown on a video screen. Ultrasound pictures or videos may be saved as a permanent record.

Why It Is Done

For men and women, pelvic ultrasound may be done to:

• Find the cause of blood in the urine (hematuria). An ultrasound of the kidneys may also be done.
• Find the cause of urinary problems.
• Look at the size of the bladder before and after urination. This can determine whether the bladder is emptying completely during urination.
• Check for growths in the pelvis.
• Guide the placement of a needle during a biopsy or when draining the fluid from a cyst or abscess.
• Check for colorectal cancer and how it is responding to treatment.

For women, pelvic ultrasound may be done to:

• Find out what is causing pelvic pain.
• Look for the cause of vaginal bleeding.
• Look for pelvic inflammatory disease (PID).
• Find an intrauterine device (IUD).
• Look at the size and shape of the uterus and the thickness of the uterine lining (endometrium).
• Look at the size and shape of the ovaries.
• Check the condition and size of the ovaries during treatment for infertility.
• Confirm a pregnancy and whether it is in the uterus. Pelvic ultrasound may be used early in pregnancy to check the age of the pregnancy or to find a tubal pregnancy (ectopic pregnancy) or multiple pregnancy.
• Check the cervical length in a pregnant woman at risk for preterm labor.
• Check a lump found during a pelvic examination.
• Check uterine fibroids found during a pelvic examination. Pelvic ultrasound may also be done to check the growth of uterine fibroids.
• Guide a procedure to remove an ovarian follicle for in vitro fertilization.

For men, pelvic ultrasound may be done to:

• Look at the seminal vesicles and the prostate gland.
• Check for prostate cancer. Other tests, including digital rectal examination, prostate-specific antigen blood test, and prostate biopsy, may also be used.
• See if urinary problems are being caused by a prostate that is getting bigger, such as from benign prostatic hypertrophy (BPH).
• Check to see if a problem with the prostate gland may be causing infertility.