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What are fibroids?

Fibroids are benign (non-cancerous) tumours that grow in, on or outside of the wall of the uterus (womb). They usually range in size from smaller than a pea to larger than a grapefruit. There can be just one but, more often, there are more than one.

Fibroids are often described by where they are in or on the uterus: 

  • in the muscle wall (myometrial),
  • in the lining of the uterus (submucosal),
  • in the outer covering layer of the uterus (subserosal), or
  • as a stalky protrusion outside of the uterus or inside the open area inside the uterus (penduculated). 

Fibroids are also called fibroyomas, leiomyomas or myomas.

Who can have fibroids?

  • Many women may have fibroids and not know it or feel any symptoms. 
  • About 20-25% of all women have symptomatic fibroids. 
  • Fibroids are rare in women under 20 years old. 
  • Fibroids are more  common in women over 30. 
  • Women over the age of 35 have between a 20 and 40 % chance of having fibroids. 
  • Black women are 3 times likelier than other women to have fibroids. 
  • Fibroids are more common in women who are significantly overweight and in women who have never had children.
  • Fibroids are more common in women towards the end of their reproductive years, and they often shrink after menopause.

What causes fibroids?

Although no one knows the exact cause of fibroids, their growth seems to be related to estrogen and progesterone production. They tend to grow, usually slowly, with the natural levels of estrogen that rise and fall in the rhythm of the menstrual cycle. In some women with perfectly normal levels of estrogen, fibroids act like a sponge and absorb more estrogen than their neighbouring cells in the uterus. 

If you are pregnant or taking birth control pills or menopausal estrogens, fibroids may grow more quickly because of the increased estrogen level in your body. Foods that are high in estrogen, and exposure to chemicals that mimic hormones may also play a role in the development of fibroids.

How do I find out if I have fibroids?

Your health care provider might find one or more fibroids during a routine pelvic exam or prenatal ultrasound. If this happens, the provider may simply note this in your file, and may monitor this during your regular check-ups. 

However, you might be among the estimated 1 in 4 women who have fibroids that affect your quality of life and require treatment. 

Sometimes, your health care provider may do a biopsy (take a small piece of tissue) of your uterus’ lining or a laparoscopy (small incision surgery) to take a sample to be sure the fibroid is not cancerous. However, fibroids almost never develop into cancer. In fact, fibroids themselves are usually harmless, but their location and size can cause problems.

What kinds of problems can fibroids cause?

Often, there are no symptoms. In women who have gone through menopause, fibroids may shrink and cause no problems. 

The common problems caused by fibroids are: 

  • long, heavy and, sometimes, more painful menstrual periods with excessive bleeding which, in some cases, cause anaemia,
  • bleeding between periods,
  • chronic pelvic pain,
  • feeling of fullness in the abdomen,
  • problems with urination or constipation, caused by large fibroids crowding the bladder or lower intestine, and
  • pain during intercourse.

In more severe cases, fibroids may also cause: 

  • problems with fertility, and
  • repeated miscarriage.

Most pregnant women with fibroids have normal pregnancies, but are more likely to have problems during pregnancy and delivery. This can be a good thing to discuss with your doctor or midwife.

If I have fibroids, what should I be careful about?

If you have fibroids that cause a lot of discomfort, discuss this with your health care provider before taking any medication that contains estrogens, such as birth control pills or hormone replacement therapy. Your health care provider will probably want to monitor you carefully. 

Your health care provider may also recommend certain vitamins and supplements that may help your body to process and remove extra estrogens.

Some women with fibroids change their diet to eat more of the foods that are good for their fibroids, and less of the foods that are bad for fibroids.  Fibroids grow and cause more difficult symptoms when a woman’s body has high levels of estrogen. For that reason, a “fibroid diet” aims to:

  • balance estrogen levels, keeping them as low as possible by taking in less estrogen and avoiding the elements your body needs in order to produce estrogen, and, 
  • help the liver run smoothly. When your liver does not have to work hard to filter toxins in our bodies, it can process excess estrogen so the estrogen can be removed from the body. 

A fibroid diet includes:

More of these foods:

  • Fruits and whole grains: Many fruits and whole grains contain fibre that helps your bowels move. Some toxins build up in our intestines and fibre helps the body clear these out. If you don’t have regular bowel movements, then your body may ingest these toxins and this can cause stress to  your liver. Be sure to drink lots of water when eating food with fibre to help your bowels work properly.
  • Yellow, red and green vegetables: A variety of yellow, red and green vegetables provides the vitamins, mineral and natural chemicals that help the body deal with fibroids. 
  • Plant estrogens: Plant estrogens (bioflavonoids or isoflavanoids) such as soy products, are a special case. They help to block “real” estrogens in the body. But plant estrogens are still weak estrogens and eating lots of them every day can have the same effect as the “real” estrogens on your fibroids. Also, talk with your health care provider about the effects of plant estrogens when combined with Hormone Replacement Therapy or certain supplements or herbs. 

Less of these foods: 

  • High-fat foods: Cutting down on high-fat foods, especially non-organic foods, can help women with fibroids. Meat and poultry are high in fat and, if non-organic, may contain chemicals that can build up in our fat. Our bodies can use extra body fat to create more estrogen. This, in turn, stresses the liver. Reach for low fat and organic dairy products, and avoid saturated and trans fats.
  • Sugar and carbohydrates: Cutting down on sugar and carbohydrates can help with fibroids. Sugar and carbohydrates make more insulin circulate in the body which in turn makes more estrogen circulate and fuel fibroids. They can also lead to weight gain and lower levels of vitamin B (which helps the liver process estrogen).  But if you cut down on sugar, please note that many chemical substitutes, such as aspartame, have been linked to other health problems. 
  • Caffeine and alcohol: Cutting down on caffeine and alcohol can also help with fibroids. Caffeine and alcohol cause a lot of stress on the liver, preventing it from processing estrogen. They are also linked to lower levels of iron absorption which can be a problem when paired with heavy bleeding. Cutting down on both of these helps by giving the liver a chance to recover. 

Some women also cut down on personal care products and cosmetics that may contain environmental estrogens and, if necessary, they seek alternatives in organic, chemical-free products.

What treatments are available for fibroids?

If you have small fibroids, some health care providers recommend simply treating the symptoms, such as cramps, pain, or increased monthly blood loss, rather than treating the fibroids. 

To control the fibroids’ growth, your health care provider may suggest you stop taking medication that contains estrogen and may suggest alternatives. However, some health care providers may even prescribe certain hormonal birth control options to help with the heavy periods.   

Until recently, health care providers often recommended hysterectomy for women with fibroids that caused excessive bleeding. Fibroids are the reason given for an estimated one-third of the 60,000 hysterectomies performed in Canada each year. 

Hysterectomy means removing the womb and sometimes the ovaries as well. 

However, there is a growing belief in medicine that hysterectomies are not appropriate for treating fibroids and there are now other options for treating fibroids, such as: 

  • Medicated Intra-Uterine Device (IUD) is sometimes used to help with the heavy periods and to shrink the fibroids, as a way to avoid more invasive procedures. 
  • Myomectomy is surgery to remove fibroids while leaving the uterus intact. Depending on the size and locations of the fibroids, myomectomy can be done through abdominal incision, with laparoscopy or through hysteroscopic resection.
    • Laparoscopy is a small tube with a scope that is sent the uterus through a small cut in the belly button. Other small incisions may be made usually discreetly along the bikini line.
    • In a hysteroscopic resection, the scope is sent through the cervix. Small instruments may go through the same pathway as the scope.
    • Myomectomy is major surgery with a long recovery time. It may require a general or regional anaesthetic or sedative. The major problem with this method is that fibroids often return and, depending on the location of the fibroid and type of procedure used, it may be more difficult to get pregnant later because of the scar tissue.
  • Uterine fibroid embolization (UFE) is a process to shrink the fibroids. The doctor uses fibre optics to guide a tube to troublesome fibroids, and injects small plastic or gelatin particles into the blood vessels that serve the fibroids. This blocks the blood supply to the fibroids. Although UFE is less invasive than surgery, little is known about its long-term effects, especially on future fertility.
  • Hormone therapy, such as Lupron or "GnRH agonist", mimics menopause to shrink fibroids temporarily. Many health care providers only recommend this treatment for up to six months, because it may also cause symptoms of menopause and bone thinning. 

While these different methods exist, it may be difficult to find a surgeon who can perform them in Canada. To find out if a particular procedure is available to you, speak to a fertility specialist or radiologist.

Where can I find more information? 

  • The first year: fibroids: an essential guide for newly diagnosed by Johanna Skilling, Marlowe & Company 2002
  • Fibroids: the complete guide to taking charge of your physical, emotional, and sexual well-being by Johanna Skilling, Marlowe & Company 2006
  • The UNhysterectomy: Solving Your Painful, Heavy Bleeding Without Major Surgery by Holly Bridges, Self-published 2012 - Book review

This FAQ may provide medical information, but is not meant to be a substitute for medical advice. When you have questions about your health, it is always advisable to ask a health care practitioner.

Revised March 2013.