What are fibroids?

Fibroids are very common benign (non-cancerous) lumps of tissue made up of an overgrowth of the uterine muscle. The overgrowth forms a lump in the muscle layer and may be big enough to protrude outwards (towards the abdominal cavity) or inwards (towards the uterine cavity). About 80% of women have at least one fibroid.

Fibroids are not cancerous or otherwise harmful to your health, and you will only need treatment if they cause you problems. If needed, they can be removed surgically. For small fibroids, this can be done with a straightforward day surgery keyhole procedure. For larger fibroids or fibroids located in more complex places in the uterus, removal is more complicated, and your surgeon will discuss it with you.

Symptoms of fibroids

Fibroids can cause problems such as increased menstrual bleeding, a sensation of pressure if they are very bulky, and – in rare cases – potential fertility issues. But many women who have fibroids do not even know they have them, and experience no symptoms.

Common queries about fibroids

Are there clinical problems associated with fibroids?

The most common problem associated with fibroids is heavier menstrual bleeding. Fibroids may distort the uterine architecture and affect blood flow, causing an increase in bleeding.

Other problems associated with fibroids will usually arise if the fibroids are large. Big fibroids can press on the bowels at the back of the uterus and cause bowel habit changes, such as constipation. If they press on the bladder at the front of the uterus you may experience urinary symptoms such as needing to urinate quickly. Occasionally, fibroids become so big that you will be able to feel them by rubbing on your abdomen. Large fibroids like this can cause pain or a sensation of pressure, but they are generally painless.

Fibroids, even very big ones, rarely cause infertility. Very occasionally they may cause problems with implantation or miscarriage, but many women with fibroids go through their pregnancies without any problems.

Can fibroids turn cancerous?

In almost all cases, fibroids are benign. The risk of fibroids turning into cancer is less than 1%. If fibroids grow in size rapidly, doctors may consider that there is a risk for cancer transformation. However, when fibroids are removed for this reason, they are rarely found to be cancerous when tested.

There is also a very rare type of ‘cancerous fibroid’ (leiomyosarcoma) that is thought to arise independently, and not develop from a benign fibroid.