A sonohysterogram is a test used to evaluate the uterus. It is performed in our ultrasound room and combines transvaginal ultrasound with instillation of a normal saline solution into the uterine cavity. A small plastic catheter (a hollow tube) is connected to the container of saline solution and then inserted through the vagina into the uterus.
The saline solution is introduced into the uterus until it is sufficiently dilated to allow careful examination of the uterine structures and lining while using the transvaginal ultrasound probe. A picture of the uterus then appears on the ultrasound monitor so the physician can evaluate the condition of the uterus. A copy of this image can be printed for your records so that comparisons are easily made. The test takes about 10 minutes to complete.
Why is it done:
Transvaginal ultrasound is the best method to evaluate the female pelvis, but it is of limited value in assessing the interior and lining of the uterus. When combined with the use of fluid solution to define the uterus, however, it is an effective diagnostic tool. It is used to evaluate abnormal bleeding, infertility, and recurrent pregnancy loss.
It can also distinguish abnormalities such as polyps and uterine fibroids and clearly identify their size and location. Abnormal bleeding can be caused by many factors, including a fibroid or polyp or hormonal imbalance. These conditions are traditionally diagnosed by an endometrial biopsy, a D&C, or a hysteroscopy. Sonohysterogram provides a safe and accurate diagnostic alternative in many instances.
Oftentimes, an endometrial biopsy is still needed to rule out pre-cancerous or cancerous tissue, or to identify a hormonal imbalance. Endometrial biopsy is especially important for women with abnormal bleeding over the age of 35. However, if there is a clear anatomic problem seen on the sonohysterogram, like a fibroid or polyp that warrants surgical removal, the office biopsy could be foregone and done instead at the time of scheduled surgery. Infertility is sometimes caused by problems in the reproductive tract.
In addition to the presence of polyps and fibroids, the sonohysterogram can also diagnose scarring of the inside lining of the uterus and some congenital (birth) uterine defects. Birth defects of the uterus do not usually cause infertility but may cause pregnancy loss. Fibroids and scarring may block the fallopian tubes and result in infertility. Endometrial polyps (polyps that arise from the endometrium, the inner lining of the uterus) do not usually cause infertility, although they are often found in infertile women.
A sonohysterogram cannot determine whether or not the tubes are open—this requires a radiologic test called a hysterosalpingogram. Recurrent pregnancy loss is diagnosed after three consecutive miscarriages and occurs in about 1 percent of women. Of these, approximately 10-15 percent have a uterine abnormality such as a uterine fibroid that can be accurately diagnosed with sonohysterogram. Regardless of fertility considerations, sonohysterogram is a convenient and efficient way to track fibroid size and growth over time.
When is it done:
Your sonohysterogram should be performed in the first half of your menstrual cycle, after bleeding has stopped but before ovulation. We do not want to perform the test while you are actively bleeding or if you should be unexpectedly pregnant. Many conditions are best visualized when the lining of the uterus is thin, before ovulation occurs.
We recommend that you take 600-800 mg of ibuprofen one hour prior to your appointment since some patients report mild cramping and discomfort during the test. You will be fine to return to work after the test or drive yourself home. It is not usual to experience slight spotting or bleeding after the test for up to a day or two. There is also a slight risk of infection.
Sonohysterography is performed here in the office without radiation, x-ray contrast, or anesthesia. It is safe, quick, and cost-effective. It is the preferred diagnostic tool for uterine abnormalities and also provides information about the exterior of the uterus and the ovaries. The information gained from a sonohysterogram may help to avoid surgery or additional testing that could be necessary following standard ultrasound procedures.
Medical evidence supporting this test:
In general, medical evidence has found sonohysterography to have much greater specificity than traditional ultrasound in diagnosing intrauterine conditions. Studies agree that its effectiveness approaches that of surgery (hysteroscopy, a camera used to look inside the uterus), but is much less invasive and less costly. Its efficacy and cost-effectiveness have been shown in both pre-menopausal and postmenopausal women. The information gained from sonohysterography cannot only help diagnose the problem, but can also help your surgeon plan a surgery if needed.