Uterine fibroids revisited

By Dr Madhu P Singh, MD (Gynaecology & Obstetrics)

The word fibroid in a gynaecologist’s office evokes images of cancer, bleeding and at the very least surgery in the minds of the patients. The real picture may be far from any of these.

Fibroids are not cancerous tumours as a rule. An extremely small percentage of fibroids would actually undergo cancerous changes. The real figures are, probably, 0.26% fibroids amongst those women that have surgery. If all women that have fibroids including those that are unaware of them, are included, the number of fibroids undergoing cancerous changes would be much lower.

Fibroids are excessive growths of the smooth muscle cells in the womb wall. The name fibroid is a misnomer, as they consist of smooth muscle and should be referred to as Leiomyomas.

People often talk of big fibroids, some as big as a watermelon.

The fact is that the size of the fibroid is not as important as the location of the fibroid.

Fibroids may be found:

–  on the outer surface (subserous);

–  within the muscle wall (intramural);

–  just beneath the inner lining of the womb or endometrium (submucous).

The fibroids that are most likely to cause problems such as heavy bleeding or miscarriages are those that lie beneath the inner lining or the endometrium.

The problems most frequently associated with fibroids are as follows:

1.  heavy, regular periods – usually painless;

2.  a feeling of weight or a dragging sensation – caused by large fibroids;

3. rarely, irregular bleeding with pain when the fibroid that lies beneath the lining being expelled by the womb – similar to the process of expulsion of the baby by contractions;

4.  repeated miscarriages or an inability to conceive.

Heavy menstrual bleeding

This is caused by fibroids that lie just below the inner lining of the womb.

The cause of the heavy bleeding is:

1.  increased surface area of the lining due to a projecting fibroid, therefore more lining sheds with a period;

2.  the lining of the womb is thicker in these women due to locally increased oestrogen levels which are associated with fibroids.

Pain is not a common feature with such fibroids unless associated with tubal inflammation (PID).

A feeling of weight

This is usually due to larger fibroids in any location due to mechanical pressure. If the fibroids are extremely large they may sometimes prevent the emptying of the urinary bladder or cause back pressure on the kidneys by compressing the urinary tubes (ureters) leading to the bladder.

Irregular bleeding and severe pain

This can only be attributed to fibroids in a non-pregnant patient if the fibroid is submucous and is projecting through the mouth of the womb (fibroid polyp) in the process of the womb trying to expel it.

The cause of the bleeding in this case is due to infection and ulceration of the surface of the fibroid.

Miscarriages

Fibroids may cause a miscarriage by preventing the growth of the baby by virtue of their sheer size and physical presence.

For the patient trying to conceive

Fibroids do not prevent pregnancy unless they are physically blocking the opening of the tubes. However as explained above they may cause miscarriages. If a patient has been unable to conceive for more than one year she is considered infertile. If such a patient has fibroids, especially submucous fibroids, they should be removed before subjecting her to medication for infertility.

Small fibroids in the muscle or on the outer surface of the womb do not cause infertility and should not be removed.

In pregnancy

Fibroids when large – more than 5 cm – may undergo degeneration where they  become soft and fleshy and cause pain. This pain should be managed or it may cause uterine contractions causing a miscarriage.

Most fibroids do not produce problems in pregnancy and most women with fibroids go through many pregnancies blissfully unaware of their presence.

Reasons for surgery

All women who have fibroids do not need surgery. The ones that do need surgery are:

1.  women with heavy menstrual cycles to the point where it is producing significant anaemia;

2.  women with irregular uterine bleeding with a fibroid polyp;

3. Infertile patients and patients with recurrent pregnancy losses (miscarriages).

Suspicion of cancerous change

Suspicion of cancerous change arises when a fibroid is growing rapidly. The point to be remembered here is that most women with a uterine mass even if it is rapidly enlarging do not have cancerous transformation in a fibroid.

Medical management of fibroids

Apart from the common surgical options of removing fibroids (myomectomy) or removing the womb (hysterectomy) several non-invasive, medical options are available.

1. The contraceptive pill

As most women are aware the contraceptive pill has many uses besides contraception. It is quite a miraculous little pill. In women with fibroids that cause heavy periods, use of the pill will make the inner lining of the womb thin and reduce the bleeding.

2. Progesterone releasing, Intra Uterine Contraceptive Device (MIRENA)

These are effective in reducing the menstrual blood loss. If there is a fibroid lying just under the inner lining, the fibroid should be removed first preferably by hysteroscopy.

3. Progestrone implants and pills

They also cause a thinning of the lining and reduce the bleeding and there is some evidence that they may reduce fibroid formation in black women.

4. GNRH Analogs, MIFEPRISTONE etc

These are expensive and have a limited application in our setting.

To summarize:

The number of women that have fibroids is very high. However the number of women that have problems that can be directly attributed to the fibroids is very low.

All fibroids do not need to be surgically removed.

The incidence of cancer in fibroids is extremely low. There is no documented, substantial risk of cancer even in a rapidly growing fibroid. However a rapidly growing fibroid in a woman who has attained menopause, should arouse suspicion.

There is effective medical treatment that is cheap and available in Guyana to treat bleeding associated with fibroids.

Due to the large numbers of ultra sound exams being done on women for reasons that may have little or nothing to do with the womb, a large number of small fibroids are being diagnosed.

Once again, remember that not all fibroids need surgery and that medical treatment is effective and available to control the bleeding associated with fibroids.