The Mirena Coil and Submucous Fibroids

The Mirena coil has been a great invention that in most instances effectively stops women having significant periods. The majority of patients with dysfunctional uterine bleeding i.e. bleeding for which there is no specifically definable cause, get enormous benefit from this device. Some women however do not do so well on it and may be sensitive to the progesterone etc. which it excretes.

This can also apply to patients who have submucous fibroids (that is fibroids which protrude into the cavity of the uterus and affect the lining of the womb) that cause heavy bleeding. Unfortunately, experience shows that the Mirena coil is ineffective in the majority of patients with submucous fibroids causing menorrhagia and also with significantly sized intramural (in the wall) fibroids which are causing heavy bleeding by increasing the size of the endometrial cavity. Again, these patients are best treated with fibroid embolization after which a Mirena coil can be successfully employed to remove their periods. After fibroid embolization, the Mirena coil should not be inserted for at least 6 months as otherwise there may be a danger of infection at the time of insertion of the device.

Submucous fibroids are fibroids which although developing in the wall, are very close to the endometrium and bulge into the cavity of the uterus to a variable degree. The problem with this type of fibroid is that they invariably cause very heavy periods: they grow under the influence of oestrogen and the periods get worse and worse, the anaemia becomes more and more problematical and the quality of life for the patient is progressively impaired. Gynaecologists may try treatments such as the Mirena coil or endometrial ablation where the lining of the womb is burned off, but these rarely or never work in the case of submucous fibroids. The best treatment for these fibroids, if they are not small and cannot be resected hysteroscopically, is fibroid embolization. This procedure is very rapidly effective, the fibroid is killed and shrinks and patients normally feel completely cured within three months of the procedure.

Sometimes, these submucous fibroid detach from the wall of the uterus and the uterus starts to contract to pass them out. Because these fibroids are dead, they can be easily removed hysteroscopically leaving the patient, if that is the only problem, with a normal uterus. In the main though these fibroids will simply die and shrink. The success rate of fibroid embolization in these patients (plus or minus hysteroscopic resection) is well over 95%. Very often I see patients who have staggered on with these symptoms, in some cases having multiple blood transfusions, because they have only been offered hysterectomy by the gynaecologist. These patients are rapidly cured by embolization and are always very pleased with the procedure and wonder why they did not have it before.

The moral of the story is: If you have this type of fibroid, which can be easily classified on ultrasound or MRI study, don’t delay treatment and, unless that fibroid is very small and can be resected easily hysteroscopically, fibroid embolization is rapidly curative and life transforming.