Causes of Fibroids

Adenomyosis

When the lining of the uterus grows into the wall of the uterus, the condition is called adenomyosis. Adenomyosisis often confused with fibroids, which frequently leads to inappropriate treatment. Normally, when the endometrium sheds during a menstrual period the blood is free to drain out through the cervix. When the lining goes into the muscle some of the blood may be trapped. When extensive, this may cause severe cramps and heavy bleeding. This can cause the walls of the uterus to thicken and the uterus to become enlarged. Often an enlarged uterus from adenomyosis is misdiagnosed as being from fibroids. Usually ultrasound or MRI can tell whether a uterus is enlarged from fibroids or from adenomyosis. Many times adenomyosis can be seen at hysteroscopy.

Adenomyosis

Note thickened wall of uterus which can be mistaken for fibroids.

Endometrium has grown into the wall of the uterus.