Fibroids are noncancerous growths in the muscle tissue of the uterus that develop attached to or within the walls of the uterus. Fibroids often appear and may enlarge during a woman’s reproductive years. Also called leiomyomas, fibromyomas, fibromas, myofibromas or myomas, uterine fibroids range in size from seedlings (undetectable by the human eye) to bulky masses that distort and enlarge the uterus.

Fibroids may remain relatively small and cause no symptoms, or they may become enlarged and cause many symptoms. A woman may have one fibroid or many of varying sizes. Many women don’t know they have fibroids until their health care provider discovers them incidentally during a pelvic exam or prenatal ultrasound. In some cases, fibroids shrink during menopause and symptoms resolve.

Symptoms generally depend on the exact type, location and size of the fibroid(s). Women may have many types of fibroids at the same time. The different types of fibroids include:
  • Intramural Fibroids: The most common type, these fibroids grow within the muscle wall of the uterus. Symptoms include heavy menstrual bleeding, pelvic pain, back pain, frequent urination, and a sense of pain or pressure in the pelvic region.
  • Submucosal Fibroids: Grow from the uterine wall into the uterine cavity. These fibroids can cause heavy menstrual bleeding, painful cramps and infertility.
  • Subserosal Fibroids: Grow from the uterine wall to the outside of the uterus. These fibroids can push on the bladder, bowel or other pelvic organs, causing bloating, abdominal pressure, frequent urination, constipation, cramping and pain.
  • Pedunculated Fibroids: The least common type, these fibroids grow on stalks out from the uterine wall into the uterus. If these stalks twist, they can cause pain, nausea, fever or (rarely) infection.
  • Track your menstrual cycle. Fibroids often cause heavy menstrual bleeding and bleeding that lasts longer than normal. To manage minor pain and bleeding, use over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen.
    Maintain a healthy weight. Being overweight or obese slightly increases a woman’s risk of fibroids.
  • If you already know you have fibroids, you should have regular pelvic examinations and ultrasounds. This monitoring enables you to keep tabs on the size of the fibroid(s) and determine if you need additional treatment.

  • Pay attention to your iron intake. Fibroids that cause heavy bleeding can deplete the body of iron, leading to anemia. Good dietary sources of iron include beans, lentils, tofu, baked potatoes, cashews, dark green leafy vegetables (e.g., spinach and kale), fortified cereals, clams, mussels, oysters, beef, pork, poultry and fish.
  • Eat a healthy diet high in fruits and vegetables, whole grains and lean proteins. Some research indicates that eating a lot of ham and red meat, such as beef, may lead to an increased risk of fibroids.

  • Aim for at least 30 minutes of moderate exercise three times a week.
  • Hormonal contraceptives: Hormonal contraceptives include birth control pills, patches and vaginal rings. These can help manage heavy bleeding caused by fibroids.
  • Gonadotropin-releasing hormone (Gn-RH) agonists and antagonists: These drugs will shrink fibroids by blocking hormone production by the ovaries. Also used to treat severe endometriosis, these drugs create an artificial menopause with decreased or elimination of menstrual bleeding. Menstrual periods and the ability to get pregnant return when medication stops.
  • Progestin therapy: A synthetic progesterone that is available in a variety of forms, including an intrauterine device with levonorgestrel, contraceptive implant, contraceptive injection or progestin pill. Intrauterine devices are not recommended for women whose fibroids significantly distort the shape of the endometrial cavity or extend into the uterus.
  • Tranexamic acid: A non-hormonal medication taken to decrease the flow of heavy menstrual periods, it’s only taken on heavy bleeding days.

Minimally Invasive Surgical Procedures:
  • Laparoscopic or robotic myomectomy: The surgical removal of fibroids while leaving the uterus in place. In this procedure, the surgeon uses slender instruments inserted through small incisions in the abdomen to remove the fibroids from the uterus. Robotic myomectomy gives the surgeon a magnified, 3D view of the uterus, offering more precision, flexibility and dexterity. This procedure doesn’t prevent a woman from having children. On the contrary, it may improve a woman’s chances of getting pregnant—though a pregnant woman who has had a myomectomy may need to deliver via cesarean birth.
  • Hysteroscopic myomectomy: May be an option if the fibroids are contained inside the uterus (submucosal). Similar to a laparoscopic myomectomy, it requires no incision, as the surgeon accesses and removes the fibroids using instruments inserted through the vagina and cervix into the uterus.
  • Uterine artery embolization: Technique used to shrink fibroids in women who are not concerned with preserving fertility. In this procedure, the blood vessels to the uterus are blocked using small particles (embolic agents). These particles cut off blood flow to the fibroids, causing them to shrink and disappear. Complications are not common but may occur if the blood supply to the ovaries or other organs is impacted. Most women resume normal menstrual periods after the procedure.
  • Endometrial ablation: An option for women who are not concerned with preserving fertility, this treatment, performed with a specialized instrument inserted into the uterus, uses heat, microwave energy, hot water or electric current to destroy the lining of the uterus, either ending menstruation or reducing menstrual flow. This procedure does not affect fibroids outside the interior lining of the uterus.

Traditional Surgical Procedures:
  • Abdominal myomectomy: Most commonly used for women with multiple fibroids or very large fibroids. Fibroids from the uterine wall are removed through an incision in the abdomen. Scarring after surgery may affect future fertility.
  • Hysterectomy: Remains the only proven permanent solution for uterine fibroids, but ends a woman’s ability to have children. Most of the time, this can be performed in a minimally invasive surgery using vaginal, laparoscopic or robotic surgery and removing the uterus through the vagina or through small incisions in the abdomen, even when the uterus is quite enlarged. Sometimes, especially with certain risk factors, the uterus needs to be removed through a larger incision in the abdomen. The method used usually depends on the size and location of the fibroids.
What are fibroids?
Fibroids are noncancerous growths of muscle tissue that occur in or on the walls of the uterus. Detectable fibroids are extremely common and range in size from small, pea-sized growths to more than 5-6 inches wide. They may remain very small for a long time, suddenly grow rapidly (for instance, during pregnancy) or grow slowly over a number of years.

How common are fibroids?
Fibroids are extremely common. In fact, by the time women are 50 years old, 80% will have fibroids—but many never know it. Only 20% of women with fibroids ever experience symptoms.

What causes fibroids?
What triggers the formation of fibroids isn’t clear, but female hormones (estrogen and progesterone) and genetics both play a big role in the growth of fibroids. Some scientists speculate that fibroids develop from misplaced cells present in the body before birth.

What are the risk factors for fibroids?
Risk factors include age, race, a family history of fibroids, obesity and high blood pressure. The primary risk factor is age—the older you are, the more likely you are to have and develop fibroids. In addition, African American women are more likely than white women to have fibroids and are more likely to develop them at a younger age.

Can fibroids cause cancer?
Uterine fibroids are not associated with an increased risk of uterine cancer and almost never develop into cancer. Rarely (in less than 1 in 1,000 fibroids), a cancerous fibroid will occur. This is called leiomyosarcoma.

Can fibroids cause infertility?
Fibroids may cause infertility, although other causes are much more common. Since it is estimated that only about 10% of infertile women have fibroids, other factors should be explored before fibroids are considered as the cause of a couple’s infertility. When fibroids are thought to be a cause, many women are able to become pregnant after the fibroids are treated or removed.

Can fibroids affect pregnancy?
Small- or medium-sized fibroids are unlikely to pose a risk to pregnancy. In rare cases large or multiple fibroids may contribute to miscarriage (delivery before 20 weeks gestation), preterm birth (delivery before 37 weeks gestation) and breech birth (in which the baby is delivered in a position other than head down). Most of the time, fibroids do not cause pregnancy complications, though about 40% of fibroids do grow larger during pregnancy because of higher hormone levels and increased blood flow to the uterus.

What causes fibroids to shrink during menopause?
Fibroids shrink during menopause due to lower estrogen and progesterone levels. Using hormone therapy during menopause will not cause fibroids to grow but may delay shrinkage of fibroids in some women.

How can I prevent fibroids?
Although researchers continue to study fibroids, the exact causes of fibroids are still unknown. So, little scientific evidence is available on how to prevent them. However, certain healthy lifestyle choices can cut down on fibroid risk, including maintaining a healthy weight, losing weight if you are overweight, and eating a diet high in fruits and vegetables. Some research suggests that using hormonal contraceptives may be associated with a lower risk of fibroids, but these results are not consistent across all study populations and more research is needed.