What are fibroids?

Fibroids are benign growths or tumours on the muscular part of the uterus (womb). They are not cancer. Fibroids can be very small or bigger than a grapefruit, and they can grow in various positions on the uterus. The symptoms a woman has will depend on the number, size and position of the fibroids. Other names for fibroids are leiomyomas or myomas.

Who gets fibroids?

Twenty-five to 40% of women of childbearing age have fibroids. They are more common in women who are overweight or in women who are having trouble becoming pregnant. Most fibroids are diagnosed when women are between 30 and 40 years of age. They are often found when a woman is being examined during pregnancy or when having a cervical smear.

What causes fibroids?

It is not known what causes fibroids. Fibroids are more likely to grow when there are high levels of oestrogen [estrogen] in the body. This explains why fibroids tend to grow during pregnancy, when oestrogen levels increase, and why they reduce in size at menopause, when oestrogen levels fall.

There is some evidence that women are more likely to have fibroids if other women in the family have had them.

Symptoms of fibroids

Many women do not know they have fibroids as they have no symptoms. Others can have symptoms which include:

• Heavy or irregular bleeding. Fibroids are often the cause of heavy periods for women in their 30s and 40s. The heavy loss of blood can lead to tiredness and anaemia (low iron levels).
• Painful periods. Sometimes, when a woman has her period, there are strong contractions as the uterus tries to push out fibroids growing inside it.
• Pain in the lower abdomen, pelvis or back. Fibroids can cause pain by pressing on internal organs or by being connected to other organs by scar tissue.
• Passing urine more frequently or having difficulty having a bowel motion. Fibroids can press on the bladder or bowel causing women to pass urine more frequently or to have difficulty in passing a bowel motion. Sometimes the pressure can be uncomfortable or painful.
• Swelling of the lower abdomen. This can happen when fibroids are large.

A woman who has any of these symptoms regularly should check with her doctor to find out the cause and to look at possible treatments.

Diagnosing fibroids

Many women are sensitive about the reproductive area of their body and find it difficult to talk about. For Maori women, the uterus is considered tapu. Many other cultures also consider the uterus to be sacred. When women are going to see their doctor or health professional about anything to do with the uterus, they may like to take a support person with them.

Not all growths in the uterus are fibroids. If a few small fibroids are diagnosed, a woman who has no symptoms may not need to be seen again. If symptoms do develop, she should tell her doctor.

If the doctor is concerned about the size of a woman's uterus, she should be referred to a gynaecologist to discuss options for treatment.

Fibroids and pregnancy

A pregnant woman who has fibroids should be referred by her midwife or doctor to an obstetrician. She may not need ongoing specialist care unless she gets symptoms during the pregnancy.

If a woman does become concerned about symptoms that develop, such as pain or bleeding, she should ask to see an obstetrician.

Methods of diagnosing fibroids

Ultrasound scan

Ultrasound scanning is an effective way of diagnosing fibroids and showing if anything is abnormal. It should be the first method used. An ultrasound scan is done by placing a hand-held device on the woman's lower abdomen or by putting a rod-like instrument into the vagina (transvaginal ultrasound). Often both methods are used. High frequency sound waves produce a picture on a monitor. Some women find having a vaginal scan uncomfortable. Women may like to take a support person with them when they have it done.

Hysteroscopy

Hysteroscopy is a surgical procedure to look inside the uterus. It is carried out under local or general anaesthetic. The uterus is filled with gas to allow a better view. A tiny telescope with a camera is put through the vagina into the uterus. A video picture is shown on a monitor. A small sample of the lining of the uterus is taken for testing.

Magnetic resonance imaging (MRI) and computed tomography (CT)

MRI and CT are scans that look at soft tissue of the body. They are used when an ultrasound scan has not given a clear result or when more information is needed. An MRI or CT scan should not be used as a first test for fibroids.

Treatment of fibroids

There are various ways of treating fibroids. The method used will depend on the number and type of fibroids a woman has, and her symptoms. It will also depend on her age and, where possible, what treatment she prefers. Fibroids can be treated with the use of drugs (medically), or by having an operation (surgically). Sometimes both methods are used. New treatments are being developed which give women more choice.

The advantages and disadvantages of different treatments need to be talked about with the doctor and weighed up. The advice given to women can vary among doctors. Some women may find a second opinion helpful.

Medical treatments

In some cases, treating problem fibroids medically can reduce the need to have an operation. However, few medical treatments have been shown to help women with fibroids in the long term. Medical treatments include:

GnRHa (see glossary)

Gonadotrophin-releasing hormone analogue (GnRHa) is a hormone treatment, which can shrink fibroids. It should not be used for more than six months as it has unpleasant side-effects such as hot flushes and vaginal dryness. It also causes bone thinning. Sometimes it is given for three months followed by treatment with oestrogen plus progestogen. A woman may want to consider either of these treatments if she does not want surgery or if surgery is not advisable. Once treatment stops, the fibroids will return to their former size.

Gestrinone

Gestrinone is a hormone treatment that shrinks the endometrium (the lining of the uterus). It is effective in reducing the size of the uterus and fibroids. It can cause symptoms such as increased growth of facial hair and deepening of the voice.

Danazol

Danazol is a synthetic hormone used to shrink the endometrium. It is not as effective as GnRHa for shrinking fibroids. Taking danazol can cause increased growth of facial hair and deepening of the voice.

Mifepristone (RU486) (see glossary)

Mifepristone is a synthetic steroid effective in shrinking fibroids without causing bone thinning. It is not yet approved in New Zealand for treating fibroids.

Medical treatments not effective for fibroids

Non-steroidal anti-inflammatory drugs (NSAIDs)

Drugs such as high-dose aspirin, Voltaren and Nurofen (NSAIDs) may be given to reduce inflammation, pain and prostaglandin levels. Although NSAIDs are sometimes given for heavy periods, they are not effective in reducing blood loss in women who have fibroids. However, they may be used to lessen pain.

Progestogens or the progesterone contraceptive pill

Progestogens or the progesterone contraceptive pill are hormone treatments that are not proven to be effective in the treatment of fibroids, although they may reduce blood loss during periods.

Hormone therapy (HT/HRT)

Hormone therapy (HT), also known as hormone replacement therapy (HRT), is a menopausal hormone treatment that is not effective in reducing the size of fibroids. Women with fibroids should particularly avoid using HT skin patches as they can increase the size of fibroids.

Surgical treatments for fibroids

There are several ways of treating fibroids surgically. The best method will depend on the type, size and position of the fibroids.

Hysterectomy

Hysterectomy is an operation where the uterus (womb) is removed. It can be performed through the lower abdomen or the vagina. A hysterectomy will remove any fibroids and therefore all symptoms of fibroids. Complications can occur after a hysterectomy, though most last a short time only. Doctors and women's health groups have information about this operation.

Compared with other countries, New Zealand has a high rate of hysterectomy. Some doctors advise a hysterectomy for fibroids in preference to other options. Others will recommend this operation only if other treatments are not suitable or have not been successful. The advantages and disadvantages of having a hysterectomy need to be discussed with your doctor.

Hysteroscopic resection

Hysteroscopic resection is a procedure that removes the lining of the uterus with an electrically heated wire and, in doing so, can remove small fibroids. A hysteroscopic resection is an alternative for women with submucosal fibroids (see diagram) or for those who have heavy or abnormal periods. It will reduce or stop the bleeding for most women.

During this operation, the uterus is filled with fluid to give a clear view. In rare cases, fluid can be absorbed into the body causing a fluid overload. This can give temporary discomfort. Bleeding and damage to the wall of the uterus can occur occasionally during the surgery.

Myomectomy

Myomectomy is an operation suitable for removing some kinds of fibroids without removing the whole uterus. It is usually done through a cut in the lower abdomen. It may be done using a laparoscope (see glossary). It is an alternative to having a hysterectomy for women with subserosal and intramural fibroids (see diagram) and symptoms such as heavy periods.

Fibroids removed by myomectomy may grow back. This happens to about 25% of women within 10 years of having the operation. Myomectomy is not recommended for women who wish to have children in the future, because there is an increased risk of the uterus rupturing during pregnancy or labour.

Fibroids and menopause

Fibroids will often get smaller and fewer at the menopause. Women at this stage may decide not to have surgery as their symptoms are likely to stop soon. During this time they may consider using medical treatments or the IUS (intrauterine system, details further below) which controls bleeding as well as giving birth control.

New treatments - surgical and non-surgical

New treatment techniques are being tried and some look promising. As yet, not enough research has been done to make clear recommendations on their use, but women could discuss them with their doctor. The new treatments include:

Myolysis

In myolysis, an electric current or laser is used under general anaesthetic to destroy a fibroid.

Cryomyolysis

Cryomyolysis is a technique used to freeze a fibroid.

Embolisation

In embolisation, the blood vessels that supply blood to the fibroid are destroyed by burning or by blocking them with polyvinyl acetate (PVA).

Intrauterine system (IUS) that releases hormones

The IUS is an IUD (intrauterine device) that releases progestogen. It may reduce heavy periods and prevent a fibroid developing. It is not yet proven to be effective at reducing the size of fibroids. An advantage of the IUS is that it may reduce a woman's chance of needing surgery or using other medical treatments.

Complementary treatments

Some women report that they have found some complementary therapies helpful. These have included herbal preparations, rongoa Maori, homeopathic remedies and lifestyle changes. As yet they have not been fully tested.

Glossary (of terms not explained in text)

• ABDOMEN - part of the body between the chest and pelvis.
• ENDOMETRIUM - lining of the uterus (womb) that is shed each month during a menstrual period.
• FIBROID - non-cancerous growth attached to the muscle of the uterus. Also called myoma or leiomyoma.
• GnRHa (gonadotrophin-releasing hormone analogue) - prevents the body producing oestrogen, causing a menopause-like state.
• GONADOTROPHIN (gonadotrophic hormone) - hormones released by the pituitary gland that cause the reproductive organs to produce sex hormones and ova (eggs). 
• GYNAECOLOGIST - doctor who specialises in the treatment of women's reproductive problems.
• IUD (intrauterine device) - small plastic or metal device inserted into the uterus.
• IUS (intrauterine system) - IUD that releases progestogen.
• LAPAROSCOPE - surgical instrument with a light which enables operations to be performed through a small cut in the abdomen.
• MIFEPRISTONE (RU486 ) - drug that reduces levels of the hormone progesterone.
• OBSTETRICIAN - doctor who specialises in the care of women with complications of pregnancy and childbirth.
• OESTROGEN [ESTROGEN] - hormone produced by the ovaries that is essential for maintaining a woman's reproductive system and her ability to have children.
• PROGESTERONE - hormone produced by the ovaries to prepare the lining of the uterus in case a baby is conceived.
• PROGESTOGEN - synthetic form of progesterone.
• PROSTAGLANDIN - hormone-like substance which causes contractions of the uterus.
• RONGOA MAORI - holistic system of Maori healing using karakia (prayer), herbal medicines and counselling.
• ULTRASOUND - method of looking at the body's internal organs by using sound waves to produce pictures on a screen.

Original material provided by Women 's Health Action Trust. It is based on a New Zealand evidence-based guideline and has been endorsed by the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG), the Royal New Zealand College of General Practitioners (RNZCGP) and the New Zealand Guidelines Group, July 2001. Reviewed by everybody, May 2011.