Management of uterine fibroids

Management of uterine fibroids

July 2002 Women's Health Update

Cindy Farquhar of National Women's Hospital reports on a new guideline.

In 1999 an evidence-based guideline on the management of uterine fibroids was produced by a small working party of health professionals and consumers for the New Zealand Guidelines Group (NZGG). The guideline is for general practitioners, obstetricians and gynaecologists as well as for women. Both the Royal New Zealand College of General Practitioners and the Royal Australia and New Zealand College of Obstreticians and Gynaecologists have endorsed it. The full document, including all of the recommendations, grading of the evidence, evidence tables, and the appendices is available on the NZGG web site: http://www.nzgg.org.nz/guidelines/0063/Uterine_Fibroids.pdf

Fibroids

Fibroids are benign smooth muscle tumours found in the submucous, intramural and/or subserosal regions of the uterus. It is estimated that 25-40% of women of reproductive age have fibroids although most have no symptoms.

Fibroids are the most common reason for hysterectomy and 10 to 15% of women will undergo hysterectomy for fibroids between the ages of 25 and 64 years. Problematic symptoms include infertility, pelvic pain and discomfort and abnormal uterine bleeding. Findings suggest that the site of the fibroid may be important in determining symptoms.

Summary of recommendations

Women who have fibroids (where the uterus is less than 16 weeks in size) but no symptoms generally require no further investigations once other causes of a pelvic mass have been excluded. Women who have fibroids detected during pregnancy and asymptomatic women with fibroids larger than the size of a 16-week uterus should have specialist referral.

Assessment procedures

A range of diagnostic procedures can be used. Transvaginal ultrasound and transvaginal sonohysterogram are both more accurate in diagnosing the location of fibroids than hysteroscopy. In about 40% of women the use of transvaginal sonohysterography can obviate the need for hysteroscopy .

There is insufficient evidence to recommend CT scanning in the assessment of fibroids. MRI should be considered for women in whom the location or nature of the fibroids remains uncertain after transvaginal ultrasound and transvaginal sonohysterography but not as an initial diagnostic test. Trans-abdominal ultrasound may be required for uteri greater than 12 weeks' size.

Medical treatments

Women with symptoms from fibroids may opt to use medical therapies to avoid surgery, or to reduce the size of the fibroids prior to surgery. Fibroids will often return to their pre-therapy size if the medical treatment is stopped.

Mifepristone (RU486) is effective in reducing uterine fibroid size without causing a reduction in bone mineral density. Gonadotrophin-releasing hormone analogue (GnRHa) treatment effectively reduces uterine and fibroid size but unpleasant side-effects and a reduction in bone mineral density limit its use to 6 months. Gestrinone is effective in reducing uterine and fibroid size but androgenic side effects may also limit its use

There is no evidence of any benefit of using progestogens or hormone replacement therapy (HRT) in the treatment of uterine fibroids. Oral contraceptives are not effective in shrinking uterine size but may help reduce menstrual blood loss. Nonsteroidal anti-inflammatory drugs (NSAIDs) are not effective as a treatment for women with fibroids in reducing heavy menstrual bleeding.

Danazol should not be recommended as initial treatment for fibroids as it is not as effective as GnRHa and has androgenic side-effects.

Surgical management

Surgical management depends on the location and number of the fibroids and the woman's symptoms. In some cases ablation or resection or myomectomy can be offered as alternatives to hysterectomy. Some women wish to preserve their ability to have children.

Embolisation of uterine fibroids may be an effective alternative to myomectomy or hysterectomy but randomised controlled trials are needed to clarify this. There is insufficient evidence to support the introduction of laser induced interstitial thermotherapy, myolysis or cryomyolysis technique.

In conclusion

For the recommendations in the guideline to be implemented, there is a need for less intervention where there is no evidence of any benefit. Fibroids are rarely life threatening and few women absolutely must undergo surgery. There are few medical therapies that are effective in the long term. There are now alternative options to hysterectomy for fibroids that require surgical intervention. Increasing GP access to ultrasound services and increased utilization of transvaginal sonohysterograms will be beneficial in establishing the site of a fibroid. This will allow better planning of uterine conserving surgical techniques.

The guidelines provide a useful reference for women and practitioners. It is now possible for women to make an informed decision about the appropriate management of a fibroid, based on evidence.