What Are Fibroids?

Fibroids are the most common growths in a woman's reproductive system. Many women with fibroids have no symptoms at all, while others have symptoms ranging from heavy bleeding and pain to incontinence or infertility.

These information pages explain what fibroids are, how they can affect your health and what your options are for treatment. For more information on heavy bleeding or hysterectomy, visit our pages on these topics.

Fibroids are tumors that grow in the uterus (womb). They are benign, which means they are not cancerous, and are made up of muscle fibre. Fibroids can be as small as a pea and can grow as large as a melon. It is estimated that 20-50% of women have, or will have, fibroids at some time in their lives. They are rare in women under the age of 20, most common in women in their 30s and 40s, and tend to shrink after the menopause.

Although the exact cause of fibroids is unknown, they seem to be influenced by estrogen. This would explain why they appear during a woman's middle years (when estrogen levels are high) and stop growing after the menopause (when estrogen levels drop).

According to US studies, fibroids occur up to nine times more often in black women than in white women, and tend to appear earlier*. The reason for this is unclear. Also women who weigh over 70kg may be more likely to have fibroids. This is thought to be due to higher levels of estrogen in heavier women.

In the past, the contraceptive pill was thought to increase the risk of fibroids, but that was when the pill contained higher levels of estrogen than it does today. Some studies suggest that the newer combined pill (estrogen and progestogen) and the mini pill (progestogen only) may actually help prevent or slow the growth of fibroids.* This information is based on studies involving black and African American women. The papers do not identify more specific ethnic backgrounds. We found no similar UK studies.

Types of Fibroids

Fibroids are categorized by where they grow in the uterus:


These grow in the wall of the womb and are the most common type of fibroid.


These fibroids grow from the outer layer of the womb wall and sometimes grow on stalks (called pedunculated fibroids). Subserous fibroids can grow to be very large.


Submucous fibroids develop in the muscle underneath the inner lining of the womb. They grow into the womb and can also grow on stalks which, if long enough, can hang through the cervix.


Cervical fibroids grow in the wall of the cervix (neck of the womb) and are difficult to remove without damaging the surrounding area. If you have fibroids, you may have one or many. You may also have one type of fibroid or a number of different types.

Fibroid Symptoms

It is estimated that 75% of women with fibroids do not have symptoms, therefore many women don't know they have fibroids. Whether or not you have symptoms depends on the size of the fibroids and where they are in your womb. This also affects the types of symptoms you are likely to have. For example, a small fibroid in the wall of your womb probably won't cause any problems, whereas a large fibroid growing outward from your womb might press against your bladder, causing bladder problems.

The most common symptom of fibroids is heavy menstrual bleeding. Other symptoms include abdominal pain or pressure, changes in bladder and bowel patterns and, in some cases, infertility.Heavy menstrual bleeding (menorrhagia)Heavy bleeding may involve flooding (a sudden gush of blood), long periods or passing large clots of blood. Heavy bleeding is not always due to fibroids, but when it is, it is usually associated with fibroids that grow into the womb (submucous). Although it is unclear exactly why fibroids cause bleeding, it may be that they stretch the lining of the womb, creating more lining to be shed during a period.

Heavy bleeding can be distressing and can make every day activities difficult. You will need to use extra sanitary protection and will probably need to change towels or tampons frequently. Some women with heavy bleeding feel they need to stay near a toilet during their periods. This can greatly restrict activity and may be frustrating or tiring.Anaemia (iron deficiency)Some women with fibroids and heavy bleeding develop anaemia as a result of blood loss. Anemia can make you feel weak, dizzy and tired. If blood tests show that you have anemia, ask your doctor about supplements or changes in your diet that might help. Foods such as liver, leafy green vegetables, dried fruit and even red wine can help boost your iron levels.Pain and pressureSome women with fibroids experience painful periods, dull aches in their thighs, back pain or constant pressure in the abdominal area that feels like bloating or fullness.Pain during your period may be due to large clots of blood pushing through your cervix. Cramps could also be caused by the womb trying to force out a submucous fibroid that is growing on a stalk in the cavity of the womb.

Large fibroids can make the womb big and bulky, which can lead to lower back pain or pelvic discomfort. Some women with fibroids feel a dull ache in their thighs or develop varicose veins in their legs. This happens when fibroids become so large they press on nerves and blood vessels that extend to the legs.Occasionally, fibroids can cause sudden severe pain in the pelvic area or lower back. This may be due to a fibroid on a stalk (pedunculated) that has become twisted. This kinks the blood vessels in the stalk and cuts off the blood supply to the fibroid. If you feel sudden severe pain and also have a fever or feel sick, you should see your doctor.

The fibroid may need to be removed or your doctor may recommend bed rest and painkillers until the pain stops on its own. Pain during sexFibroids that press on the cervix or hang through the cervix into the vagina can make penetrative sex painful and can also cause bleeding during sex. Bladder and bowel symptomsLarge subserous fibroids (on the outer part of the womb) can press on your bladder or bowel, leading to one or more of the following symptoms:


  • Frequent need to urinate
  • Leaking or dribbling urine
  • Urgent need to urinate, often passing only a small amount
  • Difficulty or inability to pass urine - this is very serious and you should tell your doctor as you may need urgent care. A tube, called a catheter, will be put into your bladder to empty it.
  • Cystitis caused by trapped urine that becomes infected bowel
  • Constipation
  • Hemorrhoids (piles)

Fibroids and Pregnancy

Most fibroids do not get in the way of a pregnancy. They may cause discomfort, but they generally do not cause any other problems. Some fibroids in certain areas, however, can make conception difficult or lead to miscarriage. Fibroids may press against, or block the entrance to, the fallopian tubes, thus preventing the egg from reaching the uterus. Submucous fibroids that grow inwards into the womb are thought to cause recurrent miscarriage. A fibroid can also interfere with labour and birth if it blocks the passage to the birth canal. If this is the case, your doctor may recommend a Caesarean section. Fibroids may increase your risk of bleeding heavily after birth, and can increase the time it takes for your womb to return to its normal size. Just as fibroids can affect pregnancy, pregnancy can affect fibroids. It is thought that fibroids grow during pregnancy because of higher levels of oestrogen, but there is little evidence to support this.

Another effect of pregnancy on fibroids is something called 'red degeneration.' This is when a fibroid's blood supply is cut off, causing it to turn red and die. It can also happen outside of pregnancy but it usually occurs in the middle weeks of a pregnancy. Red degeneration can cause intense abdominal pains and contractions of the womb, which could lead to early labour or miscarriage. If you feel these symptoms, tell your doctor. The pain and contractions usually stop on their own but your doctor may give you drugs to ease the pain and stop the contractions more quickly.Fibroids are never removed during a pregnancy because of the risk of haemorrhage (bleeding).

Prevention of Fibroids

As the cause of fibroids is still unknown, there are no clear guidelines for preventing them. However, there are some things you could do that may help reduce your risk:

  • Keep your weight in check. This will minimise oestrogen levels in your body
  • Eat green vegetables and fruit, and avoid red meat. An Italian study found that women who eat little meat but a lot of green vegetables and fruit seem to be less likely to develop fibroids than women who eat a lot of red meat and few vegetables
  • Some studies suggest the combined pill may protect against fibroids by keeping hormone levels from peaking and falling. The pill comes with its own set of side effects, however, so talk to your doctor about whether it's right for you.

Testing For Fibroids

Because there are often no symptoms, you may only find out you have fibroids when you go for an internal examination. If you have symptoms and think you might have fibroids, see your doctor. You may be referred to a gynaecologist who should be able to diagnose whether you have fibroids or another condition. The doctor will give you a vaginal examination to feel your uterus for lumps or bulges.If your doctor says you do have fibroids, ask if there is more than one, where they are and how large they are. This will help you better understand your symptoms and decide what action to take, if any. Your doctor may want to confirm a fibroid diagnosis with additional tests:

Ultrasound scan

An ultrasound uses sound waves to get an image of your internal organs. This can help determine if the lumps are fibroids or another type of tumour. It can also provide more detailed information about the size and location of fibroids. You may be given an abdominal ultrasound, a vaginal ultrasound or both. An abdominal ultrasound is best at finding large fibroids. Before your appointment you will be asked to drink up to a litre of liquid so that you have a full bladder for the test. The scan itself is not painful (the doctor simply moves the probe over your belly), but waiting for your appointment with a full bladder may be uncomfortable. A vaginal ultrasound is used to find small fibroids. The scanner (probe) will be put into your vagina and may be a little uncomfortable. You do not need to have a full bladder for this scan and it should not be painful.If the ultrasound results are unclear, your doctor may suggest a hysteroscopy or laparoscopy.


A hysteroscopy examines the inside of your womb by using a small telescope (hysteroscope) which is inserted into your womb through your vagina. Hysteroscopy can also be used to take a biopsy (tissue sample) of the lining of the womb. You may be given a local anaesthetic, general anaesthetic or in some cases, neither. If you do not have an anaesthetic, the procedure may be slightly painful. Hysteroscopy is done in hospital and you can usually go home the same day.


Whereas a hysteroscopy (see above) looks at the inside of the womb, a laparoscopy looks at the size and shape of the outside of the womb. It can also be used to take tissue samples. The procedure involves making a small cut (about 1cm wide) in the lower abdomen, just below the belly button, and inserting a thin telescope (the laparoscope). You may also have a probe inserted into your vagina to help move your womb so the laparoscope can see it from different angles.The operation usually takes about 30 minutes and is done in hospital. You will be given a general anaesthetic before the procedure and will have a few stitches afterwards. Sometimes air is pumped into the abdomen as part of the procedure and this may leave you feeling bloated.

Living With Fibroids

The most common approach to fibroids that are causing heavy bleeding is to monitor rather than treat them. You will probably be asked to have regular check-ups, but you may still want help with your symptoms.Self-helpAlthough a healthy diet may not reduce your fibroids, it may help reduce some of the symptoms:·Avoid alcohol, sugar and saturated fats. They make it difficult for your body to regulate hormones. This can increase cramps and bloating. ·Eat fruits and vegetables, particularly broccoli and spinach - they also may help your body regulate its oestrogen levels. ·Get plenty of B vitamins, calcium, magnesium and potassium - thought to help reduce cramps and bloating.

Treatments For Fibroids

If you have fibroids that are not causing you any problems, you don't need treatment. Your doctor may suggest you keep an eye out for any changes, or s/he may ask you to have regular ultrasounds to check if the fibroids are growing. If your doctor does suggest treatment, it will depend on several factors, including the severity of your symptoms, the size and position of your fibroid(s), your age and whether or not you want to have children in the future. If you are nearing the menopause, for example, when fibroids tend to shrink on their own, you may want to wait and see if your symptoms improve without treatment.

Treating fibroids has traditionally meant undergoing major surgery, but now there are other options to consider (see table below). Talk to your doctor about treatment options. Ask for a full explanation of each approach, including the risks, benefits and success rates. You may also want to talk with women who have had the treatment you are considering.

Drug Treatments

GnRH Analogues

A group of drugs, called GnRH analogues, reduce oestrogen levels in your body and, as a result, cause fibroids to shrink. Studies have shown that when taken for six months, GnRH analogues can reduce the size of fibroids by up to 50%. They also stop menstrual bleeding and pelvic pain. But GnRH analogues should not be taken for more than six months in total and there are a number of side effects. These include menopause-like symptoms such as hot flushes, vaginal dryness and bone loss (osteoporosis). Once you stop taking the drugs, fibroids begin to grow again.Your periods should also return within a few weeks, although some women may no longer ovulate after treatment.GnRH analogues are most commonly used to reduce the size of fibroids before surgery.

In some cases, doctors may recommend them as a temporary treatment for women who are nearing the menopause, when fibroids should begin to shrink naturally.Surgical and non-surgical procedures.

The main treatments for fibroids are:

  • Myomectomy (removing fibroids individually, leaving the womb intact)
  • Hysterectomy (removing the womb entirely)
  • Uterine artery embolisation (blocking the blood supply to the fibroids) These are discussed in detail below.

There is also a new procedure that is not included in the treatment chart because it is still undergoing trials. The procedure involves inserting four specially designed needles through the abdomen. Magnetic resonance imaging (MRI) is then used to guide the needles directly to the fibroid. The MRI is also used to monitor the effects on normal tissue around the fibroid in order to prevent any damage during the procedure. Once in place, the needles release laser energy into the centre of the fibroid, burning its tissue and halting its growth. Results so far suggest this procedure is effective in reducing symptoms and fibroid size, is minimally invasive and is without complications. These are, however, only the first set of results. More research and longer follow-up is needed to fully understand the benefits, risks and long-term effects.

Treatment Options for Fibroids

Abdominal Myomectomy

What is an abdominal myomectomy?

Open surgery to remove fibroids (also called laparotomy)

What types of fibroids does it treat?Can remove fibroids in the wall of the womb (intramural) and in the outer layer of the womb (subserous)

How is abdominal myomectomy surgery performed?

A cut is made in the abdomen for the doctor to shell out the fibroids. This is done with a looped wire, knife or laser. Once the fibroids have been removed, the uterus and abdomen are stitched up. The operation requires general anaesthetic and you will be in hospital for a few days.

What is the recovery period following abdominal myomectomy surgery?

It will take about a month or more to recover at home. You will probably feel tired and weak and will need to regain your strength by walking and doing specific exercises. Do not lift heavy objects while recovering.

Will the fibroids come back after an abdominal myomectomy?

Some studies show a 10-15% chance of fibroid regrowth, while others estimate 30%. In black women, regrowth may be as high as 50%.

Will I still be able to get pregnant after an abdominal myomectomy?

Most women can still become pregnant after a myomectomy, but in some cases scarring in the womb can cause fertility problems.

What are the advantages of the abdominal myomectomy procedure?

Your womb is left intact and you may still be able to have children.

What are the possible complications and other disadvantages to consider?

Bleeding that can lead to an emergency hysterectomy. Infection. Damage to surrounding organs. Disadvantages: 20 - 25% of women undergo additional surgery, usually hysterectomy, to stop symptoms. Possible weakening of the womb wall and scarring may cause complications during pregnancy such as rupturing of the womb wall.

Laparoscopic Myomectomy

What is it?

Keyhole surgery (through the abdomen) to remove fibroids.

What types of fibroids does a laparoscopic myomectomy address?

Recommended for fewer than four fibroids and fibroids that are less than 10cm wide.

How is a laparoscopic myomectomy performed?

A laparoscope (telescope) is inserted into the womb through a tiny cut in the abdomen. Other small cuts are made in the same area to insert instruments that slice up and remove the fibroids. This is done under general anaesthetic and you will be in hospital for a day or two. It is a difficult, often long, procedure and requires a highly skilled surgeon.

What is the recovery period following a laparoscopic myomectomy?

The surgery may take longer but recovery is much quicker than abdominal myomectomy. Recovery at home takes 7 - 14 days.

Will the fibroids come back after a laparoscopic myomectomy procedure?

This procedure may not remove all fibroids. Any missed fibroids are likely to continue to grow. New fibroids may also develop.

Will I still be able to get pregnant?

Laparoscopic myomectomy does not usually interfere with fertility.

What are the advantages of having a laparoscopic myomectomy?

Less invasive than other surgical options. Small abdominal scars and little scarring inside the womb.

What are the possible complications and other disadvantages of this procedure?

Unexpected complications may require an abdominal myomectomy or emergency hysterectomy. There may also be an increased risk of your womb rupturing during pregnancy.

Hysteroscopic Myomectomy

What is a hysteroscopic myomectomy?

Removal of small fibroids through the vagina.

What types of fibroids does a hysteroscopic myomectomy address?

Can remove only small submucous fibroids.

How is a hysteroscopic myomectomy performed?

A small hysteroscope (telescope) is inserted into the womb through the vagina and cervix. A laser or wire loop is then inserted through the hysteroscope to remove the fibroids. You will be given a general or local anaesthetic and will probably be able to go home the same day.

What is the recovery period following a hysteroscopic myomectomy procedure?

It should take 2 - 7 days to recover at home.

Will the fibroids come back after a hysteroscopic myomectomy?

There is a 20-30% chance of fibroids growing back.

Will I still be able to get pregnant following a hysteroscopic myomectomy?

Hysteroscopic myomectomy does not usually interfere with fertility.

What are the advantages of a hysteroscopic myomectomy?

No incisions. Recovery is less than a week. Little scarring. You will still have your womb and may be able to have children.

What are the possible complications and other disadvantages?

Possible damage to the womb wall. Symptoms may continue: one study showed that after three years, heavy bleeding had returned in 30% of women who had a hysteroscopic myomectomy.

Uterine Artery Embolisation

What is uterine artery embolisation?

A new procedure that blocks the blood supply to the fibroids. This reduces rather than removes fibroids.

What types of fibroids does a uterine artery embolisation address?

There has not been enough research to determine which types of fibroids respond best to embolisation.

How is a uterine artery embolisation performed?

The radiologist (doctor) threads a fine tube into the right and left uterine arteries and injects a dye to locate the arteries that are feeding the fibroids. A special substance is then injected to block (embolise) the blood supply. This is done under a local anaesthetic and you will be in hospital for a couple of days.

What is the recovery period following a uterine artery embolisation?

Recovery at home should take 1 - 2 weeks.

Will the fibroids come back after a uterine artery embolisation?

There is little information about fibroid regrowth after embolisation.

Will I still be able to get pregnant if I have a uterine artery embolisation?

Some women have become pregnant after embolisation, but it can also lead to ovarian failure. More research is needed.

What are the advantages of the uterine artery embolisation procedure?

Minimally invasive. No incisions or scars. Quick recovery period. You will still have your womb and may be able to have children.

What are the possible complications and other disadvantages of this procedure?

Risk of infection that requires a hysterectomy. Risk of ovarian failure. Radiation exposure. May cause ovarian failure. This is a very new procedure and long-term effects are still unknown.


What is a hysterectomy?

Removal of the uterus (womb). In some cases, the fallopian tubes, cervix and/or ovaries are also removed.

What types of fibroids does a hysterectomy address?

Removes all fibroids. Should only be done if fibroids are very large or cause problems that cannot be treated in other ways.

How is a hysterectomy done?

The uterus is removed either through a cut in the abdomen (if fibroids are large) or through the vagina (if fibroids are small). Both are major operations. Abdominal hysterectomy can take one hour or several depending on the size of fibroids. You will be in hospital for 5-7 days. Vaginal hysterectomy takes about an hour and you will be in hospital for 2-3 days.

What is the recovery period following a hysterectomy?

Abdominal hysterectomy - Recovery will take 6 - 8 weeks at home. Vaginal hysterectomy - Recovery should take about 5 weeks at home. You will feel tired but try to walk as much as possible.

Will the fibroids come back after a hysterectomy?

Fibroids will not grow back.

Will I still be able to get pregnant if I have a hysterectomy?

If you have a hysterectomy you will not be able to have children.

What are the advantages of the hysterectomy procedure?

All of your fibroids will be gone and will never grow back.

What are the possible complications and other disadvantages?

Possible damage to your bladder or bowel. Infection. Risk of bleeding heavily during or after the operation, which may require a blood transfusion. You will no longer have your womb or be able to have children. Can lead to an early menopause.