They are benign (non-cancerous) growths that occur in the uterus (womb), and they happen because muscle mass in the uterine wall overgrows, perhaps because of over-sensitivity to oestrogen. Fibroids can range from pea-sized to the size of a grapefruit, and usually more than one grows at the same time. Some fibroids just grow in the wall of the uterus, others protrude into the uterine cavity, and still others grow away from the wall on a stalk. A few grow in the cervix. Most fibroids grow slowly over a period of time and are oestrogen sensitive, so they get bigger during pregnancy (when there are high levels of oestrogen in the body) and shrink after the menopause (when oestrogen levels drop).
Who gets fibroids?
They are very common, with as many as one in five women over the age of 30 having them; they are most common in women in their 40s. Fibroids rarely occur in women under the age of 20. They are also more common in black women and in women who have had no children, or only one child. Endometriosis is often also present.
What are the symptoms?
Fibroids are often symptomless and may only be found during a routine gynaecological examination. If there are symptoms, they may include:
* Abdominal swelling or bloating – may cause a feeling of discomfort
* Heavy periods
* Problems passing urine or the need to pass urine frequently – fibroids may be pressing on bladder
* Abdominal pain – fibroids can sometimes break down or a fibroid that has grown into the uterine cavity on a stalk may become twisted
* Recurrent miscarriage or infertility – fibroids can sometimes (rarely) stop an embryo from developing very far or may prevent a fertilised egg from implanting in the lining of the uterus in the first place.
Are fibroids a problem?
They are only a problem if they are causing problems; as already stated, most do not cause any symptoms and are only discovered by accident. If you are pregnant and have fibroids, then your baby is likely to be monitored regularly as they can squeeze the baby during the later stages of pregnancy and may make labour difficult; a Caesarean section may be required to deliver the baby. Very rarely a fibroid may become malignant (cancerous) so they are always monitored regularly.
What is the treatment?
It can be difficult to diagnose fibroids, especially if you are pregnant at the same time. If the fibroids are not causing any symptoms or you are approaching the menopause (when fibroids often start to shrink) it is likely that no treatment will be pursued. If the fibroids are very troublesome and you have completed your family, then a hysterectomy is one option. If you have not completed your family, then you may be given hormone medication in order to try and reduce the size of the fibroids, although some fibroids do not respond to hormonal treatments. Another option might be a myomectomy, when one or more large fibroids are removed leaving the uterus intact. However, it is not unknown for fibroids to start to bleed heavily during a myomectomy, which means that a hysterectomy will have to be performed. Even if your fibroids are treated successfully, younger women may find that further fibroids can then start to grow.