Fibroids

Published by Bupa's health information team, June 2008.

This factsheet is for women who have fibroids, or who would like information about them.

Fibroids are non-cancerous growths of the womb (uterus). They are also known as uterine myomas, fibromyomas or leiomyomas.

• About fibroids
• Symptoms
• Complications
• Causes
• Diagnosis
• Treatment
• Further information
• Questions and answers
• Related topics
• Sources

About fibroids

More than one in three women have fibroids, but most of these women don't ever get any symptoms.

Fibroids are enclosed in fibrous capsules attached to the wall of your womb and don't spread to other parts of your body.

You can have one fibroid or many - the average number is between four and seven depending on your age.

Fibroids are named according to where they are found in your womb.

• Intramural fibroids grow within the muscular wall of the womb.
• Subserous fibroids grow from the outside wall of the womb into the pelvic cavity. They can become very large.
• Submucous fibroids grow from the inner wall of the womb into the space inside the womb.
• Pedunculated fibroids grow from the outside of your womb. These fibroids are almost free of the wall of your womb and are only attached by a narrow stalk.

Fibroids range from the size of a pinhead to up to 20cm across.

Fibroid growth is very slow and can be stimulated by hormones, especially oestrogen. A hormone is a chemical found naturally in your body. Fibroids tend to become smaller and reduce in number when oestrogen levels fall, such as after the menopause.

The different types of fibroid

Symptoms

Fibroids don't usually cause symptoms. However, you may get one or more of the symptoms listed below, often depending on where the fibroid is within your womb.

• Heavy periods, sometimes leading to anaemia, can occur in up to a third of all women with fibroids.
• Large fibroids can lead you to feeling some pain in your tummy (abdomen).
• If the fibroid(s) is pressing on your bladder, you may need to pass urine more often than normal.
• If the fibroid(s) is pressing on your rectum, it can cause constipation.
• You can get severe pain if a fibroid growing on a stalk twists or if a fibroid outgrows its blood supply causing it to break down, but this is rare.

Complications

Fibroids and pregnancy

Most women with fibroids have a normal pregnancy and delivery. In around two-thirds of women, the fibroids stay at a constant size or shrink.

Submucosal fibroids can affect the shape and internal environment of the womb, which can make it more difficult to become pregnant.

Problems such as miscarriage, premature labour and bleeding can happen, but they are rare.

If you are pregnant and have fibroids, you should consider seeking specialist pregnancy care from an obstetrician (a doctor specialising in pregnancy and childbirth).

Fibroids and cancer

Fibroids very rarely become cancerous.

Causes

The reason why women get fibroids isn't known. Although oestrogen seems to make the fibroids grow, it's not thought to be responsible for their initial development.

You are more likely to get fibroids if you:

• are in your 30s or 40s
• are overweight
• are African-Caribbean - African-Caribbean women are three times more likely than white women to get fibroids
• have no children or had your last child at a young age
• have a family history of fibroids

Diagnosis

As fibroids rarely have symptoms, they are often found during routine gynaecological (vaginal) examination.

Your doctor may do the following tests to see if you have fibroids.

• An internal examination to check the size of your womb. An enlarged womb indicates that you may have fibroids.
• An ultrasound scan uses sound waves to produce an image of part of your body and can confirm if you have fibroids.
• Magnetic resonance imaging (MRI) scans use magnets and radiowaves to produce images inside of your womb.

Treatment

If you don't have any symptoms, or if they are only mild, you don't need treatment.

If you are getting symptoms, there is a range of treatments available. Your doctor will explain which is most suitable for you.

Medicines

There is no medicine that cures fibroids. However, hormone-based treatments can help relieve the symptoms.

Treatment with gonadotrophin releasing hormone analogues (GnRH analogues) can lower your oestrogen level. This usually shrinks the fibroids. GnRH analogues such as goserelin (eg Zoladex) or leuprolin acetate (eg Prostap SR) are often prescribed for three to four months before surgery (see Surgery) to make it easier to remove fibroids.

GnRH analogues can cause side-effects such as hot flushes and, long-term, osteoporosis (thinning of the bones). Therefore, you can only take GnRH analogues for a maximum of six months. Taking progestogen hormone replacement therapy or tibolone (Livial) at the same time reduces the chances that you will get side-effects.

Non-surgical treatments

Uterine artery embolisation (UAE)

This treatment blocks the blood supply to a fibroid, causing it to shrink. It's performed under a local anaesthetic, meaning that the feeling in the area will be completely blocked but you will stay awake during the operation.

UAE gives relief from symptoms such as bleeding and pain for at least two-thirds of women treated. Side-effects and complications with UAE are lower than with open surgery.

The National Institute for Health and Clinical Excellence (NICE) states that UAE is a relatively new treatment with uncertain long-term results. If you are considering UAE, please talk to your gynaecologist (a doctor specialising in identifying and treating conditions of the female organs).

Endometrial ablation

An endometrial ablation is a procedure to remove the lining of your womb or an individual fibroid using laser energy or ultrasound. You can still get pregnant after an endometrial ablation.

Surgery

There are a number of surgical options including those outlined below.

• A myomectomy is an operation to remove fibroids leaving the womb in place. It may be done through cuts in the tummy or through your vagina using keyhole surgery. A myomectomy is usually only offered to women who prefer the option to become pregnant in the future.
• A hysterectomy is a major operation to remove the entire womb, usually via a "bikini-line" cut in the tummy or, if the fibroids are not too large, via the vagina. It's not possible to get pregnant after a hysterectomy.

Sometimes it's possible for these operations to be performed by keyhole surgery.

Further information

• Women's Health Concern
  0845 123 2319
  www.womens-health-concern.org
• National Institute for Health and Clinical Excellence
  www.nice.org.uk

Related topics

• Anaemia - a general overview
• Endometrial ablation
• Hysterectomy - abdominal
• Hysterectomy - vaginal
• Local anaesthesia and sedation
• MRI scan
• Pelvic ultrasound

Sources

• Parker WH. Etiology, symptomatology, and diagnosis of uterine myomas. Fert Steril 2007; 87(4):725-736. www.elsevier.com
• Magnetic resonance image-guided transcutaneous focused ultrasound ablation for uterine fibroids. National Institute for Health and Clinical Excellence (NICE), 2007, Interventional procedure guidance 231. www.nice.org.uk
• Griffiths A, D'Angelo A, Amso N. Surgical treatment of fibroids for subfertility. Cochrane Database of Systematic Reviews 2006, Issue 3. Art. No.: CD003857. DOI: 10.1002/14651858.CD003857.pub2. www.cochrane.org
• Constipation. Clinical Knowledge Summaries. www.cks.library.nhs.uk, accessed 17 December 2007
• British National Formulary (BNF). BMJ Publishing Group, 2007. 54: 407-412
• Uterine artery embolisation for the treatment of fibroids. National Institute for Health and Clinical Excellence, 2004, Interventional Procedure Guidance 94. www.nice.org.uk
• Uterine artery embolisation for the treatment of fibroids. National Institute for Health and Clinical Excellence (NICE), 2004, Information from Interventional Procedure Guidance 94. www.nice.org.uk
• MR image-guided percutaneous laser ablation for uterine fibroids. National Institute for Health and Clinical Excellence (NICE), 2003, Interventional Procedure Guidance 30. www.nice.org.uk

This information was published by Bupa's health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Thomas Ind MBBS, MD, MRCOG; Royal Marsden Hospital, Fulham, London and by Bupa doctors. It has also been reviewed by Women's Health Concern. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.

Publication date: June 2008