A uterus ultrasound is a non-invasive imaging technique that allows healthcare providers to visualize the female reproductive system. This diagnostic tool assesses the health and structure of the uterus, ovaries, and surrounding pelvic organs.
Understanding the Uterus Ultrasound
A uterus ultrasound operates by emitting high-frequency sound waves from a small transducer, which is a handheld device. These sound waves travel through the body and bounce off organs and structures, returning to the transducer. A computer then processes these echoes into real-time images displayed on a monitor, providing a visual representation of the internal anatomy.
There are two primary methods for performing a uterus ultrasound: transabdominal and transvaginal. A transabdominal ultrasound involves placing the transducer on the lower abdomen, often requiring a full bladder to help visualize the pelvic organs more clearly. This approach provides a broader view of the pelvic area.
A transvaginal ultrasound uses a slender, lubricated probe inserted into the vagina, offering a closer and more detailed view of the uterus and ovaries. This method provides clearer images due to its proximity to the organs. The choice between methods depends on specific diagnostic needs.
Characteristics of a Healthy Uterus
On an ultrasound, a healthy uterus exhibits a pear-shaped appearance, measuring 7 to 8 centimeters in length, 4 to 5 centimeters in width, and 2 to 3 centimeters in thickness in non-pregnant adults. Its outer contours appear smooth and well-defined. The uterine muscle wall, known as the myometrium, has a uniform, homogeneous texture without visible masses or irregularities.
The endometrial lining, the inner layer of the uterus, undergoes cyclical changes throughout the menstrual cycle. During the early follicular phase, shortly after menstruation, it appears as a thin, bright line, measuring 2 to 4 millimeters. As ovulation approaches in the late follicular phase, the lining thickens to 7 to 11 millimeters and takes on a “trilaminar” or “triple-line” appearance.
Following ovulation, in the luteal phase, the endometrial lining continues to thicken, becoming more uniform and hyperechoic (bright on the ultrasound), reaching 8 to 16 millimeters in thickness. Normal ovaries appear oval-shaped, measuring 2.5 to 5 centimeters in length, and may show small, fluid-filled sacs called follicles, which are part of the normal ovulatory process.
Common Findings That May Indicate Issues
An ultrasound can reveal several common findings that may indicate issues. Uterine fibroids, also known as leiomyomas, are benign growths of muscle tissue that appear as well-defined, solid masses within the myometrium. Their appearance can vary, ranging from small, dark areas to larger, more irregular shapes that distort the uterine contour.
Endometrial polyps are overgrowths of the uterine lining that appear as bright, often finger-like projections within the endometrial cavity. They are seen as homogeneous, sometimes stalked masses. Ovarian cysts, which are fluid-filled sacs on or within the ovaries, present as round, anechoic (dark, fluid-filled) structures with smooth walls.
Adenomyosis involves the presence of endometrial tissue within the myometrium, causing the uterine wall to appear thickened and heterogeneous. It can also appear as small, cystic areas or streaky shadowing within the muscle layer. These findings prompt further evaluation to determine their significance.
When a Uterus Ultrasound is Recommended
A healthcare provider may recommend a uterus ultrasound to investigate symptoms related to reproductive health. Reasons include persistent pelvic pain, where the ultrasound can help identify potential causes such as ovarian cysts or fibroids. It also evaluates abnormal uterine bleeding, which includes unusually heavy, prolonged, or irregular menstrual periods.
For individuals experiencing fertility issues, a uterus ultrasound can assess the shape and structure of the uterus, identify any blockages in the fallopian tubes, and evaluate ovarian function. During the early stages of pregnancy, an ultrasound confirms the pregnancy, determines gestational age, and checks for fetal viability and location.
An ultrasound may be used to monitor previously identified conditions, such as the growth of fibroids or the resolution of ovarian cysts. It helps understand the underlying causes of symptoms and guides medical management.