Uterine fibroids (leiomyoma) are non-cancerous growths in the muscle lining the uterus (womb). They may be single or multiple in number and vary in size. Some have a stalk and are called pedunculated fibroids. Those without a stalk are referred to sessile.
What causes uterine fibroids?
The exact cause of fibroids is not known but they are dependent on oestrogen, a hormone released from the ovaries. They can therefore grow during pregnancy when levels of oestrogen rise, and shrink after the menopause when oestrogen levels fall. They are more common in women who have never been pregnant (nulliparous).
What are the typical symptoms?
Some of the common symptoms of uterine fibroids are:
- Heavy menstrual bleeding (menorrhagia) necessitating frequent changes of sanitary towels. The bleeding may also be prolonged. Sometimes the bleeding is so heavy as to cause anaemia.
- Pressure sensation in the pelvis.
- Infertility. Rarely, fibroids can interfere with the implantation of the fertilised egg into the uterus.
- Severe pain in pelvic area if the fibroids twist (called torsion).
- Frequent urination and constipation due to pressure on the bladder or bowel. If the fibroid is very big it can put pressure on the ureter, the tube that leads from the kidneys to the bladder, and lead to kidney problems
- If fibroids grow during pregnancy they can lead to complications during labour and indeed can cause premature labour. They can also be a cause of recurrent miscarriage.
Often, women have no symptoms (asymptomatic) and the presence of fibroids is picked up routinely on pelvic ultrasound.
How are uterine fibroids diagnosed?
If you present with any of the symptoms suggestive of uterine fibroids your doctor will examine your abdomen to feel for any lumps. Only very big fibroids can be detected in this way, however, and your doctor may need to perform an internal pelvic exam to feel the size and shape of your uterus.
Alternatively, your doctor may refer you for a pelvic ultrasound. This is a non- invasive procedure similar to the ultrasound carried out during pregnancy to show an image of the baby.
Uterine fibroids treatment
If the fibroid is not causing any problems your doctor will simply observe it over time and no immediate treatment is necessary. However, if the fibroid(s) is troublesome, it can be managed either surgically or medically.
Surgical treatment involves either excising the fibroid in an operation called a myomectomy or removing the entire uterus (hysterectomy). Both operations are performed under general anaesthetic. A myomectomy is the treatment of choice for women who have not yet completed their families.
Sometimes medical treatment is recommended. This involves prescribing a drug called a Gonadotrophin Releasing Hormone (GnRH) analogue, which prevents oestrogen from being produced. Without oestrogen, the fibroid will shrink in size. The drugs, however, can cause side effects similar to menopausal symptoms such as hot flushes, loss of periods and vaginal dryness. Ideally they should only be given for no longer than six months as the loss of oestrogen can lead to osteoporosis (thinning of the bones). When the drug has stopped the fibroids can grow in size again.