Because uterine fibroids often do not produce any symptoms, many women may not be aware of them. A physician, typically a gynecologist, may discover the presence of fibroids during a routine pelvic examination or while testing for another condition. Upon palpation, the uterus may feel irregularly shaped, lumpy or enlarged. This is typically indicative of fibroids. However, a physician will usually order several diagnostic tests to rule out other disorders with symptoms similar to uterine fibroids, as well as gynecologic cancers. Other conditions that may cause similar symptoms include the following:

• Endometrial polyps. Benign (non-cancerous) tumors that grow in the lining of the uterus (endometrium). Symptoms of endometrial polyps include heavy menstrual bleeding, spotting after the menstrual period or spotting that is not related to menstruation.
  
  
• Adenomyosis. In this condition, cells that normally make up the endometrium penetrate into the muscular wall of the uterus (myometrium) and may cause symptoms, such as abnormal uterine bleeding and pelvic pain.
  
  
• Ovarian cysts. Fluid-filled structures that form within or on the ovaries. Abnormal cysts are usually benign but in rare cases may be malignant. Symptoms of ovarian cysts include painful or irregular menstrual periods. A cyst that ruptures can cause severe one-sided pelvic pain.
  
  
• Hormonal imbalance. Hormones are responsible for various functions throughout the body, including regulating a woman’s reproductive functions such as the normal development of eggs in the ovaries. An absence of ovulation, which is caused by abnormal hormone signals, can cause heavy bleeding and a thickened uterine lining.

An ultrasound is the most common diagnostic test used to determine the presence of uterine fibroids. Ultrasounds are an imaging test that uses sound waves to make “pictures” of organs in the body. An ultrasound can be performed either through the abdomen or vagina (transvaginal ultrasound) and lasts about 30 minutes. Using an ultrasound, a physician can observe the shape, size and location of the fibroids.

Other tests that may be used in the diagnosis of uterine fibroids include:

• Blood tests. A physician can order analysis of a patient’s blood sample to rule out cancer, bleeding disorders and to check the levels of reproductive hormones produced by the ovaries. A blood test also can determine the presence of iron-deficiency anemia, which can result from prolonged abnormal uterine bleeding.
  
  
• Endometrial biopsy. A sample of the lining of the uterus may be obtained for laboratory analysis to rule out cancer and check for other causes of abnormal uterine bleeding.
  
  
• Other imaging tests. These tests are often useful in determining if a uterine fibroid is indeed present or if another type of tumor is present. Common imaging studies that a physician may use to examine the uterus and surrounding pelvic organs include:
  
  
• Hysteroscopy. During this test, the physician inserts a small, lighted tube (hysteroscope) through the cervix and into the uterus. The tube releases a gas or liquid that expands the uterus and allows the physician a closer view of the uterine walls and the openings of the fallopian tubes. This test is frequently performed in conjunction with an endometrial biopsy or to surgically remove a fibroid that protrudes into the uterine cavity (submucosal).
  
  
• Hysterosalpingogram. During the test, the physician inserts a small, thin tube (catheter) into the cervix. The catheter releases a contrast medium (dye) that flows into the uterus. The dye outlines the shape of the uterine body and fallopian tubes and makes any fibroids visible on x-ray images.
  
  
• Sonohysterography. Saline solution, and sometimes air, is delivered by a catheter into the uterus to help the physician observe these structures with an ultrasound. The saline expands the uterus and allows detection of fibroids and other abnormalities that may not have been visible during an abdominal or transvaginal ultrasound. When air is also injected, the presence or absence of bubbles can indicate to the physician whether there is blockage in the fallopian tubes.

Other imaging tests that may be used to detect uterine fibroids include computed axial tomography (CAT scan) and magnetic resonance imaging (MRI). These tests are not routinely needed to diagnose fibroids, but may help clarify the diagnosis in some cases.