What Is Gynecologic Ultrasonography?

Gynecologic ultrasonography, or gynecologic sonography, is the use of ultrasound imaging in order to detect abnormalities or to monitor the health of the female reproductive tract. Structures that can be examined through gynecologic ultrasonography include the uterus, ovaries, Fallopian tubes, pouch of Douglas, and adnexae. Other related structures in the pelvis, such as the bladder, kidneys, and ureters, may also be examined. The two routes of gynecologic ultrasonography are transabdominal and transvaginal. Utilization of these routes depends on the indication or need for imaging.

Medical ultrasonography is an imaging method that uses the reflection of sound to produce images of certain structures. No radiation is used, making it safer than other imaging procedures, such as radiography and computed tomography (CT). It also gives a real-time picture of structures and is relatively inexpensive. This makes it an important imaging modality in gynecology.

Ultrasonography of the female reproductive tract can be done by either placing the ultrasound probe on the abdomen or by inserting the probe through the vagina. The first route is called transabdominal ultrasound, and the second route is called transvaginal ultrasound. When a transabdominal method is used, a full bladder is desirable because fluid allows sound to travel better. An empty bladder is preferred when transvaginal ultrasonography is utilized. The transvaginal route uses a higher frequency of sound, thus it gives higher resolution images of the uterus, endometrium, and ovaries.

Gynecologic ultrasonography has various applications. It is indicated when a female patient presents with pelvic pain or bleeding, and pathologies such as endometriosis, adenomyosis, and ovarian cysts or masses are suspected. An enlarging abdomen without evidence of pregnancy and other diseases may lead a physician to suspect leiomyoma, a benign tumor of the uterus. Some gynecologic cancers, such as ovarian or uterine cancer, may be initially detected through gynecologic ultrasonography.

This procedure is an important diagnostic modality for fertility problems and pregnancy. When ultrasound is used to detect or monitor a pregnancy, it is called obstetric ultrasonography. The gestational sac can be detected as early as 4.5 weeks of gestation, and the embryo can be seen as early as 5.5 weeks of gestation when transvaginal ultrasound is used. Ultrasonography is also very important when a female patient with missed menstrual periods has severe abdominal pain and ectopic pregnancy, one not within the uterine cavity, is suspected.

Women who are undergoing fertility treatments also benefit greatly from gynecologic ultrasound. For instance, it can detect whether or not there is an increase in the number or size of ovarian follicles in response to fertility treatments. When the fertility treatment chosen is in vitro fertilization (IVF), transvaginal ultrasonography guides the retrieval of eggs or oocytes.