Fibroids, also known as leiomyomas or myomas, are benign (non cancerous) growths that occur in the muscle of the uterus.
Having fibroids is very common. Up to 80% of women will have fibroids in their lifetime. Fibroids develop when a single muscle cell in the uterus rapidly multiples to form a non cancerous growth. It is unclear why fibroids develop, but genetics are likely involved. It is also thought that hormones affect fibroid growth as often after menopause fibroids rarely grow and most often will decrease in size.
Usually fibroids are found in the body of the uterus but they can sometimes grow in the cervix. Fibroids in the uterus are divided into three categories: those located in the outside wall of the uterus (subserosal), those located in the muscle layer of the uterus (intramural), and those that go into the cavity of the uterus (submucosal). Depending upon their location fibroids can enlarge and distort the uterus.
Most often, fibroids have no symptoms and do not require any treatment. However, they can cause symptoms and require treatment depending upon their size and location in the uterus. Most common symptoms are bleeding and pelvic pressure.
Fibroids are often identified during a pelvic exam when we are assessing the size and shape of the uterus. However, depending upon the size and location of the fibroids it is possible that they may not be felt on a pelvic exam. Often an ultrasound is required for identification or confirmation of fibroids. Sometimes, a test called a hydrosonogram (also called a saline infused sonogram) will be used to evaluate the fibroids. We do this test when we are unable to tell from an ultrasound if the fibroid is near, affecting, or in the cavity of the uterus. During this test, a small catheter is placed through the cervix into the uterus. We then put sterile saline through the catheter into the uterus. While the fluid is going in we perform a transvaginal ultrasound. This test allows us to identify whether or not a fibroid is located in the uterine cavity or if it distorts the cavity of the uterus.
Most women with fibroids do not have trouble becoming pregnant from the fibroids. Fibroids are the sole reason for infertility in less than 5% of patients. Studies have shown that fibroids located inside the uterine cavity or distort the cavity can cause trouble with achieving pregnancy or having miscarriages. Due to this, when fibroids are located in the cavity or distort the cavity they often will need to be removed to optimize fertility and carrying a pregnancy. Fibroids that are located in the outer part of the uterus often do not affect fertility and only rarely require treatment. Sometimes, when no other causes for infertility are found, fibroids located in the outer part of the uterus that do not affect the cavity will be removed but only if they are very large.
While most people never require treatment for their fibroids, for those that do need treatment there are multiple treatment options. In patients actively trying to conceive that need treatment of their fibroids the only option is surgical removal of the fibroid. Thus surgery is called a myomectomy. There are different ways to do this surgery and the way it is performed depends upon the location, number, and size of the fibroids.