Uterine fibroids come in sizes from tiny to grapefruit size, and may or may not cause symptoms. Your doctor may find them on a diagnostic image that was made for some other purpose. Most often, though, Mayo Clinic doctors diagnose your fibroids after a pelvic examination and an ultrasound or magnetic resonance imaging (MRI) scan.
- Pelvic exam. After asking you about your symptoms and family health history, your Mayo Clinic doctor uses a pelvic exam to evaluate the position, size and shape of your uterus. If it's enlarged or bumpy, your doctor will probably suspect fibroids and order tests to rule out other disorders that can produce similar symptoms.
- Endometrial biopsy. If you report abnormal bleeding, your doctor may scrape a tissue sample from the lining of your uterus and send it to the laboratory for analysis. An endometrial biopsy isn't used to test for fibroids, but it can let your doctor know that other disorders, such as cancer, aren't causing your symptoms. Your doctor can do the biopsy in the office without anesthesia when performing your pelvic exam.
- Complete blood count (CBC). If you have heavy or prolonged menstrual bleeding, your doctor will order a CBC. That blood test tells your doctor whether you have iron deficiency anemia caused by chronic blood loss. If you have iron deficiency anemia, which is common with fibroids, you may need iron supplements as well as treatment for your fibroids.
- Ultrasound scanning. Ultrasound (sonography) is often the first imaging test your doctor will order to verify fibroids. The scan uses a hand-held device (transducer) that sends sound waves through your abdominal wall and vagina into your uterus. A computer converts echoes from sound waves into images so that your doctor can see your fibroids.
- Hysteroscopy. Your doctor may perform a hysteroscopy to see if your abnormal bleeding is caused by something other than a fibroid. It's an office procedure that lets your doctor look at the inner walls of your uterus. Fiber optics inside the hysteroscope's thin telescopic tube light the inside of your uterus, and a tiny cutting tool may be used to take a sample of tissue.
- Magnetic resonance imaging (MRI). Mayo Clinic doctors use MRI images to determine the number, size and precise location of your fibroids.
Read more about pelvic exam, complete blood count (CBC), ultrasound and magnetic resonance imaging (MRI) at MayoClinic.com.